Participants will receive a total of 24 in-person training sessions using three sets of eight repetitions per set on six power resistance-training exercises. During training participants will be allowed 1-minute rests between sets. Participants will come in person for up to 12 weeks, twice per week, for approximately 45 minutes per day.

Movement analyses will be performed during the ten-meter walk test. The measure will be swing time. Swing time is how long it takes to swing the back foot forward to initiate a new step. The unit of measurement is seconds.

Movement analyses will be performed during the ten-meter walk test. The measure will be stance time. Stance time is the duration of the time between heel strike and toe off the same foot. The unit of measurement is seconds.

Movement analyses will be performed during the ten-meter walk test. The measure will be double support time. Double support time is how long both feet are in contact with the ground. The unit of measurement is seconds.

Movement analyses will be performed during the ten-meter walk test. The measure will be step time. Step time is how long one foot is in contact with the ground. The unit of measurement is seconds.

Movement analyses will be performed during the ten-meter walk test. The measure will be cadence. Cadence is the number of steps per minute. The unit of measurement is steps per minute.

Movement analyses will be performed during the ten-meter walk test. The measure will be stride length. Stride length is the distance covered when a person takes two steps. The unit of measurement is meters.

Movement analyses will be performed during the ten-meter walk test. The measure will be step length. Step length is the distance covered when a person takes one step. The unit of measurement is meters.

Movement analyses will be performed during the ten-meter walk test. Gait speed is how fast a person walks. The unit of measurement is meters per second.

Movement analyses will be performed during the ten-meter walk test. Stride width is the side-to-side distance between the line of the two feet during gait. The measurement is in meters.

The five-time sit-to-stand test will be used to assess functional lower body strength. The participant will sit with arms folded across the chest and the back against the chair. On a verbal command, the participant will stand up and sit down five times as quickly as possible. Timing begins at "Go" and ends when the buttocks touch the chair after the fifth repetition. One practice and two testing trials will be performed. Time will be measured in seconds.

For the Seated Medicine Ball Throw, subjects will sit in an armless chair with the back against the chair back, while holding the 6-pound medicine ball against the chest. Subjects will then throw the ball at a perceived 45° angle as far as possible. Subjects must complete at least three practice trials; however, subjects will be allowed more trials until comfortable with the testing procedure. Upon starting the official trial, subjects will complete three separate attempts at each varying medicine ball, to nine trials in total. Each of the three trials within a given medicine ball will be separated by a 1-minute rest. Distance will be measured in centimeters.

The object of the test is to walk as far as possible for six minutes. The subject will walk at a normal pace around a marked course for six minutes. The subject may stop to rest and begin again at will. The distance covered indicates aerobic fitness. The further a person walks, the better cardiovascular condition. The units are meters.

Upon verbal cue, the subject stands up, walks around a cone placed three meters from the front edge of the chair, and then returns to a seated position as quickly as possible. Time is measured in seconds. The faster the person completes the test the better the dynamic balance.

Three images will be taken in the longitudinal view in B-mode. Muscle thickness will be measured by drawing a perpendicular line from the deep to superficial aponeurosis at the thickest region of each muscle. The unit of measurement is centimeters.

Muscle quality will be measured through ultrasound using a Gray Scale. The black and white pixels correspond to arbitrary values of 0 (darker) to 255 (lighter), with darker colors indicting more muscle and lighter colors indicating more fat.

The Parkinson's Disease Questionnaire-39 is a 39-item self-report questionnaire that assesses Parkinson's disease-specific health-related quality over the last month across the eight quality of life dimensions and specific dimensions of functioning and well-being. Each question is scored from 0-4 points, with lower scores reflecting better quality of life.