Flexibility Guidelines (ACSM)

From the American College of Sports Medicine recommendations for healthy adults (exercise to develop and maintain muscular strength and endurance, flexibility, and body composition):

Flexibility training: Stretches for the major muscle groups should be performed a minimum of 2–3 days per week; at least 4 repetitions, held for 10–30 seconds, should be completed.

A related general flexibility prescription (Musculoskeletal Conditioning, p. 216) gives:

• Frequency – daily
• Intensity – to a position of mild discomfort
• Duration – 10–30 seconds for each stretch
• Repetitions – 2–6 for each stretch
• Type – static, with a major emphasis on the low-back and hamstrings area because of the high prevalence of low-back pain syndrome in society.

That page also notes the warm-up should include light activity to raise heart rate and internal body temperature, followed by flexibility exercises stretching the musculature around the major skeletal joints; attempting to stretch a cold muscle can be dangerous to the surrounding soft tissue.

• ACSM: stretch major muscle groups a minimum of 2–3 days/week.
• At least 4 repetitions per stretch.
• Hold each for 10–30 seconds.
• General prescription (p. 216): frequency daily; intensity to mild discomfort; 10–30 s duration; 2–6 reps; static type; emphasis on low-back and hamstrings.

• flexibility-guidelines-program-standards — the program-standard counterpart (10 s hold, repeat twice, static).
• static-stretching — the recommended stretch type.
• flexibility-benefits — why flexibility matters.