Stretching Techniques of Knee Muscles and Their Effect on Joint Range, Suppleness and Muscle Activity in Elderly

Effects of Proprioceptive Neuromuscular Facilitation on Joint Range of Motion, Flexibility and Electromyographic Activity of Knee Muscles in Older Adults

The goal of this clinical trial was to compare the effect of two different types of stretching techniques in elderly population. The main questions it aims to answer are:

1. What is the immediate effect (after a single intervention) of these stretching techniques on muscle flexibility, amount of knee joint motion and muscle activity?
2. What is the effect of a four week intervention program of these stretching techniques on muscle flexibility, amount of knee joint motion and muscle activity? There were three groups with ten randomly allocated participants in each group. Intervention group I was given a stretching technique called contract-relax technique and the Intervention group II was given static stretching. The third group was not given any treatment and was taken as a control. The main aim was to find out that whether the two techniques are effective or not and which one of the two is better than the other in terms of improvement in the above mentioned parameters.

The objective of the study was to compare the effects of Proprioceptive Neuromuscular Facilitation - Contract Relax (PNF- CR) and static stretch techniques immediately and post four weeks of intervention on knee range of motion, flexibility and electromyographic activity of knee muscles among older adults. This is an outcome assessor-blinded pre-test post-test randomized controlled trial with two experimental groups (PNF-CR and Static Stretching) and a control group. 30 males aged 55-75 years were randomly assigned into PNF group (n=10), Static Stretch group (n=10) and Control group (n=10). Knee range of motion, electromyographic activity of hamstrings and sit and reach test, were taken for the dominant side thrice: pre-intervention, immediately after stretching and after the training period. Active knee range of motion (ROM) was assessed using a universal goniometer. Surface Electromyography (EMG) was used to record Maximal voluntary isometric contraction (MVIC) of biceps femoris and the Chair Sit-and-Reach Test (CART) was used to assess the hamstring muscle's length flexibility.

Inclusion Criteria:

• Male adults aged between 55 and 75 years
• Able to do activities of daily living (ADL) without assistance
• Able to comprehend and follow instructions

Exclusion Criteria:

• Grade III or IV osteoarthritis or any other musculoskeletal condition affecting the muscle length.
• History of any surgery to hip, knee, low back or ankle
• History of any medication (anti-inflammatory, for pain relief, or anti-arthritic) in previous six months
• History of life-threatening disease (neurological disease, cardiovascular disease, severe hypertension)
• Passive full knee extension (popliteal angle 180 degrees)