You’ve probably been told your whole life how important it is to stretch before engaging in moderate-to-intense physical activity. And, indeed, research from the 1980s and ’90s did actually support the notion that stretching prior to exercise would reduce one’s chance of injury.1,2 In the years since, however, many more studies have been conducted evaluating the impact stretching has on injury and performance in relation to physical exercise, with conflicting results.3,4 But most studies have failed to find a positive association between stretching and a reduction in injuries, prevention of low back pain, or delayed onset muscle soreness (DOMS).5–7
That doesn’t mean that stretching—or flexibility exercises—aren’t good for your body! Flexibility exercises have been shown to have many beneficial effects, including increased range of motion (ROM), postural stability, and balance.6,8 According to the American College of Sports Medicine(ACSM),6 adults should do flexibility exercises a minimum of two or three days each week to improve ROM. The ACSM exercise guidelines6 recommend that each stretch be held for 10 to 30 seconds at a time to the point of tightness or slight discomfort and repeated 2 to 4 times, or until 60 seconds have accumulated per stretch. The ACSM also states that flexibility exercise is most effective when the muscle being stretched is warm, and recommends light aerobic activity or a hot bath to warm the muscles prior to stretching.
TYPES OF FLEXIBILITY EXERCISES
There are four general types of flexibility exercises that can improve ROM, postural stability, and balance: Ballistic, dynamic, static, and proprioceptive neuromuscular facilitation (PNF). Ballistic stretches. Ballistic—or bouncing—stretches use the momentum of repetitive movement, i.e., bouncing, to produce the stretch in the targeted tendon/ muscle. Due to the risk of straining or pulling a muscle,9 bouncing stretches are generally not recommended for the average person just looking to stay in shape or improve flexibility. This type of stretch is often used by athletes such as dancers, football players, or martial artists to aid in increasing ROM that is required for their particular sport.
Toe touch. A common bouncing stretch is the toe touch. Here, you start in a straight standing position, then, bending at the waist, touch your fingers to your toes (or as close to your toes as you
can get) and then repeatedly bounce your torso up and down in small movements from the waist while keeping your fingers in contact with your toes.
Dynamic stretching.
Dynamic stretching, also a repetitive movement stretch, is performed as a gradual transition from one body position to another, while the reach and range of motion is continually increased as the movement is repeated several times.6 Dynamic stretches are designed to mimic the movements the targeted joints and muscles go through in a specific sport or activity. Adding weights can increase the intensity of the exercise. Walking lunge. The walking lunge is an example of a dynamic stretch. Keeping your core tight, stand with your feet shoulder width apart, hands on hips. Step one leg forward, bending at the knees as you lower your hips. Keeping your posture straight, descend until your rear knee nearly touches the ground. Your front knee should stay above the front foot (not past it). Extend your knees as you raise yourself back up. Step forward with your rear foot, repeating the lunge on the opposite leg.10 This should be repeated several times using slow, deliberate movements.
Static stretching (active and passive).
Static stretching involves slowly stretching a muscle/tendon group and holding the position for a period of time, e.g., 10 to 30 seconds. Static stretches are beneficial in improving ROM and flexibility.
There are two types of static stretching: active and passive. Active stretching involves stretching a muscle group by actively contracting one group of muscles in opposition to another group. You do not use external forces, such as a stretch band or other body part, to achieve the stretch. Usually these stretches are only held for 10 to 15 seconds. Passive stretching requires some sort of external force in order to achieve the stretch (e.g., another person or a stretching device). With passive stretches, you rely on the external force to hold the body part being stretched in place. These stretches can be held 10 to 30 seconds.
Static active stretch—triangle pose. An example of a static active stretch is the triangle pose used in yoga. Stand with legs straight and separated into a wide stance. Align your feet, with the back foot pointing at a 60-degree angle toward the front foot. Extend the right arm toward the sky and, folding in at the left hip, reach the left arm down to the ground. Both arms should be aligned with the shoulders in a straight line. Hold for 10 to 30 seconds, then straighten torso, lower arms, and then do the same motions on the opposite side.10 Repeat on each side five times.
Static passive stretch—arm stretch. An example of a static stretch would be the arm stretch. Bring one arm across your upper body, shoulder level, and hold it straight. Grasp the elbow with opposite arm and pull toward your chest. Hold for 10 to 30 seconds and repeat on opposite side.11 This stretch can be repeated five times on each arm.
Proprioceptive neuromuscular facilitation (PNF).
PNF was originally developed as a means to treat neuromuscular conditions such as polio and multiple sclerosis. According to ACSM, there are many forms of PNF, but most typically involve an isometric (i.e., a muscular action in which tension is developed without contraction of the muscle) movement of the selected muscle-tendon group followed by a static stretching of the same group (i.e., contract-relax).6
Banded leg raise. An example of a PNF stretch is the banded leg raise. For this stretch, lie down on your back and put a resistance band around one of your feet. Holding the resistance band with both hands, and keeping the leg straight, use the band to lift the leg up and pull the leg back as far as you can until you feel a stretch, keeping your knee straight. Keep the other leg on the ground. Hold it for 5 seconds, then push your leg back down to the ground against the resistance of the band.
Perform the same motions on the other leg. Repeat five times, attempting each time to pull the leg back slightly further than before.12
CONCLUSION
Joint flexibility decreases as we age, but flexibility can be improved across all age groups using stretching exercises. According to the ACSM,6 ROM can be improved after 3 to 4 weeks of regular stretching at a frequency of at least 2 to 3 times a week, and it could improve in as few as 10 sessions with an intensive program.6 Your local yoga or Pilates studio is a good place to start when choosing a flexibility program. But, for those who prefer to stretch at home, YouTube.com is a great resource. The Livestrong.com YouTube channel offers several videos demonstrating various flexibility exercises.