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Fitness head Kevin Schultz presents Fiber Content: Static Stretching 101

Hello, I’m Kevin Schultz, the director of strength and conditioning at Carnegie Mellon. This will be a bimonthly column that will feature informative and practical information regarding muscle and connective tissue fiber within your body. More specifically, I will be writing on topics regarding stretching, strength training, exercise selection, exercise prescription and planning, and cardiovascular training, as well as more general topics regarding nutrition as it relates to gains made from exercise. Without further ado, Static Stretching 101:

Most commonly, people participating in physical activity know one — and only one — way to stretch: statically. Although a lot has changed over the past 50 years regarding societal norms, technology, and stretching, static stretching still seems to be the choice for most physically active people. This is mostly true due to the ease of access to the equipment needed to perform static stretching: you.

To stretch before, during, or after exercise — that is the question. Actually, static stretching can be used at all three periods to improve flexibility, training adaptations, recovery time, and even injury prevention.

Pre-workout static stretching is typically performed on various muscle groups in order to warm up and prevent injury during a training session. Trainers recommend stretching large multi-joint muscle groups (e.g. quadriceps, hamstrings, chest, and back). Muscles should be placed under a constant, mildly discomforting stretch for 15–60 seconds depending on the number of times you will stretch each muscle. The magic number with all static stretching seems to be 60 seconds, during which you have the option of holding a stretch for one 60-second interval or up to four 15-second intervals.

During workout static stretching of the antagonist muscle — the muscle opposite the one being trained in the workout —has been shown to improve the strength of the agonist muscle — the one being trained — during a lifting session. For example, stretching out the quadriceps — the muscles on the front of the thighs — between sets of a hamstring — the back of the thigh — exercise increases the strength of the hamstrings. During an exercise set, two muscle groups are always working together to produce movement. The agonist muscle contracts to produce the movement while the opposing antagonist muscle relaxes to allow movement to happen. At times during movement, both muscles may contract at the same time, which can inhibit fluid motions.

Stretching the antagonist between sets decreases co-contraction to allow the agonist to produce slightly more force. Between each set, a muscle can be placed under stretch for 15–60 seconds depending on your goals and your programmed rest intervals.

Post-workout static stretching is probably the most widely known and performed type of stretching. Most people are aware of benefits that are attributed to static stretching, such as increased flexibility and increased range of motion (ROM), but there is one large benefit many people miss out on. During a normal training session, either strength or cardiovascular in nature, muscle fibers have a habit of shortening in length because they tend to be inflexible, and will wear down if not exercised — that is, if you don’t use it, you’ll lose it.

During a typical training session, only a very small ROM is used, causing the muscle fiber to shorten. If the natural length of the fibers is not properly restored, this shortening can lead to muscular dysfunction or injury.

Post-workout stretching is one way to decrease the chances of this happening. A short muscle cannot start to recover or rebuild until it reaches its natural resting muscle length. As with all static stretching, the goal is to stretch each trained or exercised muscle group for at least 60 seconds.

With all exercises, before you start, you should always consult your physician to gain medical clearance. If you have any specific questions, please feel free to e-mail me (schultzk@) and I will be more than happy to help you out.