The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. The conditions of practice will vary based on 1) ability to perform the activity, and 2)level of challenge the participant is faced with performing the activity during his day. Equipment will be provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. The conditions of practice will vary based on 1) ability to perform the activity, and 2)level of challenge the participant is faced with performing the activity during his day. Equipment will be provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.

The strength and flexibility exercise condition involves performance of 1) strengthening exercises that target all trunk muscles, and 2) flexibility exercises that target all trunk and lower extremity motions.

Strength and flexibility exercise: Exercises based on best evidence for effectiveness in people with chronic low back pain will be prescribed. Strengthening exercises will target all trunk muscles. Flexibility exercises will target all trunk and hip motions. All exercises will be performed at the intensity appropriate for the person's musculoskeletal fitness level based on the American College of Sports Medicine guidelines. Difficulty level, frequency, and number of repetitions will be modified based on guidelines described in the literature. Equipment will be provided as needed.

The motor skill training condition involves supervised, massed practice of novel, challenging functional activities that are difficult or painful for the participant to perform due to his low back pain.

Motor skill training: The participant will assist in selecting both simple and complex functional activities to practice. Difficulty will be graded to match the participant's motor capabilities. Three activities will be practiced per session. Within the practice of activities the training will emphasize 1) contraction of groups of specific trunk muscles, 2) earlier and greater movement of the hip, knee, and/or thoracic spine relative to the lumbar spine, 3) later and less movement of the lumbar spine relative to other regions. Within each activity the conditions of practice will vary based on 1) the participant's ability to perform the activity, and 2) the level of challenge the participant is faced with when performing the activity during his day. Equipment provided as needed.