- What is ballistic stretching
- Comparing stretching methods
- Warm-up for Sports and Exercise
- Benefits of stretching
What is ballistic stretching
Ballistic stretching or “bouncing” stretching, is dynamic stretching that involves rapid, alternating movements or ‘bouncing’ at end-range of motion; however, because of increased risk for injury, ballistic stretching is no longer recommended 1). However, ballistic stretching, when properly performed, increases flexibility similarly to static stretching, and may be considered for individuals engaging in activities that involve ballistic movements, such as basketball 2). Ballistic stretching uses the momentum of the moving body segment to produce the stretch 3). Dynamic stretching or slow movement stretching involves a gradual transition from one body position to another, and a progressive increase in reach and range of motion as the movement is repeated several times 4). A lot of people often confuse dynamic stretching with ballistic stretching. It is true that both methods of stretching require extended body movements. However, in dynamic stretching, it is not required to stretch the body muscles and tendons much beyond their usual range of motions. It does not involve movements of jerking and bouncing either.
While ballistic stretching is jerky and erratic, dynamic stretching is smooth and controlled in nature5). Health experts often advise dynamic stretching over ballistic stretching in most cases.
The main advantages of ballistic stretching exercise are:
- Improvement in Dynamic Flexibility.
- Muscles get ready for high impact activity.
- The body gets pushed beyond its comfort zone, ideal for physically intensive activities.
- Enhances motor performance of the muscles.
- A Sports Medicine study indicated that ballistic stretching improves hamstring flexibility. It can be particularly helpful for people with tight hamstring issues.
There are three muscle stretching techniques that are frequently described in the literature: Static, Dynamic, and Pre-Contraction stretches (Figure 1) 6). The traditional and most common type is static stretching, where a specific position is held with the muscle on tension to a point of a stretching sensation and repeated. This can be performed passively by a partner, or actively by the subject. Static stretching involves slowly stretching a muscle/tendon group and holding the position for a period (i.e., 10-30 s). Static stretching can be active or passive 7).
Active static stretching involves holding the stretched position using the strength of the agonist muscle, as is common in many forms of yoga. In passive static stretching, a position is assumed while holding a limb or other part of the body with or without the assistance of a partner or device (such as elastic bands or a barre). Proprioceptive neuromuscular facilitation (PNF) methods take several forms but typically involve an isometric contraction of the selected muscle-tendon group followed by a static stretching of the same group (i.e., contract-relax) 8).
Figure 1. Muscle stretching techniques
Abbreviations: Techniques of Muscle Stretching. HR = Hold relax; CR = Contract relax; CRAC = Contract relax, agonist contract; PIR = Post-isometric relaxation; PFS = Post-facilitation stretching; MET = Medical exercise therapy.[Source 9) ]
Static, dynamic, and pre-contraction stretching are all effective methods of increasing flexibility and muscle extensibility; however, these modes may be more effective in specific populations 10). Several authors have noted an individualized response to stretching 11); therefore, stretching programs may need to be individualized.
Proprioceptive neuromuscular facilitation (PNF) and static stretching elicit greater gains in joint range of motion than dynamic or slow movement stretching 12). Proprioceptive neuromuscular facilitation (PNF) may produce slightly larger gains in flexibility of some joints compared with other techniques, but it is less practical because of the need for a partner 13). However, one comparative review reported that range of motion improvements of 5-20 degrees occurred after 3-10 week of hamstring stretching irrespective of whether static or proprioceptive neuromuscular facilitation (PNF) techniques were performed 14).
Stretching after you exercise helps optimize the range of motion about your joints and boosts circulation. As a general rule, stretch your major muscle groups after you exercise. In some studies, stretching right before an athletic event has been shown to decrease athletic performance, especially before activities requiring ballistic movements, jumping or running.
Overall, however, stretching after exercise can help you to optimize your joint range of motion. If you don’t exercise regularly, you may want to stretch a few times a week after a brief warmup to maintain flexibility.
When you’re stretching, keep it gentle. Breathe freely as you hold each stretch for around 30 seconds. Try not to hold your breath. Don’t bounce or hold a painful stretch. Expect to feel tension while you’re stretching. If you feel pain, you’ve gone too far.
Moving in sport- or activity-specific motion planes in gradually progressive speed (dynamic stretching) may be a helpful complement to static stretching and may help improve athletic performance.
For a general fitness program, the American College of Sports Medicine 15) recommends static stretching for most individuals that is preceded by an active warm-up, at least 2 to 3 days per week. Each stretch should be held 15-30 seconds and repeated 2 to 4 times.
Many exercise studies on older adults include stretching exercises as part of a well-rounded exercise program. Unfortunately, there is no clear dose-response for flexibility training in older adults because stretching interventions are often combined with strengthening, balance, and cardiovascular activities, making it difficult to isolate stretching’s effectiveness. Older adults may need longer stretch times than the recommended 15 to 30 seconds; Feland et al 16) found that 60-second holds of static stretches were associated with greater improvements in hamstring flexibility in older adults compared to shorter duration holds. Ten weeks of static stretching of the trunk muscles was able to increase spinal mobility (combined flexion and extension range of motion [ROM]) in older adults 17). Static stretching of the hip flexors and extensors may also improve gait in older adults.87 Furthermore, the effectiveness of type of stretching seems to be related to age and sex: men and older adults under 65 years respond better to contract-relax stretching, while women and older adults over 65 benefit more from static stretching.
Ballistic stretching exercises
Popular ballistic stretching exercises:
- The Standing Lunge – This is one pose that can also be done in other stretching methods. It does benefit the glutes and quadriceps. You need to keep a foot forward, and the arms should be loose on the sides. You may also keep the hands totally straightened above the shoulders. Now bend the foot forward and plummet forward rapidly. The other foot should be bent behind, and the body weight should be on your heel of the foot forward. Now, return to the initial position and try the pose with the other leg.
- Another widely practiced ballistic exercise is standing upright and starting bouncing down to touch the toes that can repeatedly be done.
- There is a sitting variant of the exercise above. For that, you need to sit on a mat or floor with the upper body in the vertical pose. Now, try touching the ankles stretched in front with your hands with repeated and prompt moves.
- Side Arm Swing – This is another pose that is not too hard to try out! You need to stand with both legs slightly bent. The feet should be hip-width apart. Ensure the back is straight. Now, swing both the arms on the sides and next cross them in front.
- You can also improve chest muscle flexibility with ballistic exercise. You need to stand in an upright posture and extend both the arms to the sides and straighten them. The palms should face the roof and elbows should be little flexed. Now, you have to flex the shoulders to move the arms behind repeatedly.
- Leg Swings – This is another popular ballistic stretching posture. You need to stand sideways and keep an arm’s length from the wall. Now, put the body weight on the left leg and keep the right palm on the wall to maintain balance. Then, swing the right leg forward and backward for several rounds. This can be done on the other side too.
- Overhead Arm Swing – To try this Ballistic stretching exercise, you need to stand with the legs a foot apart and both the legs kept bent. Maintain an erect back. Now, swing both the arms repeatedly to an overhead position. Then, you can swing the arms forward and backward. Each position can be repeated a number of times, as per your comfort level.
Disadvantages of ballistic stretching
There is no denying ballistic stretching is not a risk-free form of exercise. Entities like the American College of Sports Medicine 18) advise against it. The main risks are:
- Forceful and sudden stretching movements can hurt the soft body tissues and ligaments.
- The muscles and tissues can become more susceptible to injuries.
- It can trigger stretch reflex mechanism, which actually tightens the muscles.
Before trying ballistic stretching moves, the following factors should be considered carefully:
- If the person is new to exercising and has some amount of exposure to static stretches or not.
- The age and health condition of the person.
- If the person suffers from muscle, joint or ligament related conditions.
- If the ballistic stretching moves can benefit the person in a professional capacity. For example, if he or she is an athlete and the exercise can enhance their efficacy level.
How long should a stretch be held?
Holding a stretch for 10-30 seconds at the point of tightness or slight discomfort enhances joint range of motion, with little apparent benefit resulting from longer durations 19). Older persons may realize greater improvements in range of motion with longer durations (30-60 seconds) of stretching 20). A 20%-75% maximum contraction held for 3-6 seconds followed by a 10- to 30-seconds assisted stretch is recommended for proprioceptive neuromuscular facilitation (PNF) techniques 21).
How many repetitions of stretching exercises are needed?
Repeating each flexibility exercise two to four times is effective, with enhancement of joint range of motion occurring during 3-12 week 22). The goal is to attain 60 s of total stretching time per flexibility exercise by adjusting duration and repetitions according to individual needs. For example, 60 seconds of stretch time can be met by two 30-s stretches or four 15-seconds stretches 23).
How often should stretching exercise be performed?
Performing flexibility exercises ≥2-3 days per week is effective 24), but greater gains in joint range of motion are accrued with daily flexibility exercise 25).
What types of flexibility exercises should be performed?
A series of exercises targeting the major muscle-tendon units of the shoulder girdle, chest, neck, trunk, lower back, hips, posterior and anterior legs, and ankles are recommended. For most individuals, this routine can be completed within 10 min.
When should stretching be performed?
Flexibility exercise is most effective when the muscle temperature is elevated through light-to-moderate cardiorespiratory or muscular endurance exercise or passively through external methods such as moist heat packs or hot baths, although this benefit may vary across muscle-tendon units 26).
Stretching exercises can have a negative effect on subsequent muscle strength and power and sports performances, particularly when strength and power are important 27). However, limited evidence is available about the effects of stretching programs of different durations and types (e.g., passive vs dynamic) on exercise activities with varying characteristics, particularly in individuals who are exercising for improving fitness. Further research is needed before making universal recommendations concerning the timing of stretching in association with other exercise activities. Nonetheless, based on the available evidence, whenever possible, persons engaging in a general fitness program should perform flexibility exercise after cardiorespiratory or resistance exercise-or alternatively-as a stand-alone program. For most persons, a dynamic, cardiorespiratory endurance exercise warm-up is superior to flexibility exercise for enhancing cardiorespiratory or resistance exercise (especially with high duration and repetitions) performance 28). A preevent warm-up that includes both cardiorespiratory and flexibility exercise has benefits for specific recreational sports such as dancing 29).
Comparing stretching methods
Several authors have compared static and dynamic stretching on range of motion (ROM), strength, and performance 30). Both static and dynamic stretching appear equally effective at improving range of motion (ROM) acutely or over time with training 31). Several authors have found no improvement in performance when comparing static and dynamic stretching 32), 33), 34). In contrast to static stretching, dynamic stretching is not associated with strength or performance deficits, and actually has been shown to improve dynamometer-measured power 35) as well as jumping and running performance 36).
The literature is conflicting regarding the effects of warm-up stretching prior to exercise. Static and dynamic warm-ups are equally effective at increasing range of motion (ROM) prior to exercise. Some researchers report static stretching after warm-up decreases performance 37), while others report no change or an increase in performance 38). While static stretching is generally followed by an immediate decrease in strength, static stretching performed before 39) or after warm-up 40) does not decrease strength. The volume of static stretching may also affect performance: Robbins et al 41) reported that 4 repetitions of 15-second holds of static stretching did not affect vertical jump, while 6 repetitions reduced performance.
A pre-stretch contraction has been associated with greater acute gains in ROM compared to static stretching in many studies;48,50,67–75 however, several studies show similar increases in ROM 42) and performance 43) when comparing pre-contraction stretching and static stretching. Both acute static stretching and pre-contraction stretching have been shown to decrease strength 44).
Warm-up for Sports and Exercise
Stretching performed as part of a warm-up prior to exercise is thought to reduce passive stiffness and increase range of movement during exercise. In general, it appears that static stretching is most beneficial for athletes requiring flexibility for their sports (e.g. gymnastics, dance, etc.). Dynamic stretching may be better suited for athletes requiring running or jumping performance30 during their sport such as basketball players or sprinters.
Stretching has not been shown to be effective at reducing the incidence of overall injuries 45). While there is some evidence of stretching reducing musculotendinous injuries 46), more evidence is needed to determine if stretching programs alone can reduce muscular injuries 47).
Stretching is a common intervention performed during rehabilitation. Stretching is prescribed to increase muscle length and ROM, or to align collagen fibers during healing muscle.
Several researchers have investigated different muscle stretching techniques on subjects with tight hamstrings. Some authors report that both static and pre-contraction stretching are able increase acute hamstring flexibility 48), while others suggest static stretching 49) or proprioceptive neuromuscular facilitation (PNF) stretching 50) are more effective. It appears that 6 to 8 weeks of static stretching is sufficient to increase hamstring length 51).
Stretching is effective for the treatment of orthopedic conditions or injury; however, as with other populations, outcomes may be based on the individual patient. Static stretching has been shown to be more effective than dynamic stretching for those recovering from hamstring strains 52). In addition, it has been reported that athletes with hamstring strains recover faster by performing more intensive stretching than by performing less intensive stretching 53). Patients with knee osteoarthritis can benefit from static stretching to increase knee ROM 54); however, proprioceptive neuromuscular facilitation (PNF) stretching may be more effective 55). Chow et al 56) reported that total knee replacement patients benefited from 2 weeks of either static, dynamic or proprioceptive neuromuscular facilitation (PNF) stretching to increase ROM.
Stretching is often included in physical therapy interventions for management of shoulder, back and knee pain. Despite positive outcomes of these types of studies and improvements in flexibility, it is difficult to isolate the effectiveness of the stretching component of the total treatment plan because the protocols usually include strengthening and other interventions in addition to stretching.
A recent review98 of stretching for contractures found no improvement in joint mobility orthopedic-related contractures. Orthopedic contractures often result from shortness in non-contractile tissues such as capsuloligamentous structures rather than muscle tightness.
Researchers have shown that 12 months of stretching is as effective as strengthening exercises or manual therapy in patients with chronic neck pain 57). In addition, patients with chronic musculoskeletal pain demonstrate an increased tolerance to stretch after 3 weeks of static stretching 58). Lewit and Simons 59) reported an immediate 94% reduction in pain associated with trigger points after applying a post-isometric relaxation (PIR) technique. These studies support stretching in pain management programs.
Stretching appears to have no benefit for neurological patients who have had a stroke or spinal cord injury 60). Because of a strong neurological component and long-standing muscle shortening associated with these conditions, it’s no surprise that simple muscle stretching techniques are not effective.
Benefits of stretching
Studies about the benefits of stretching have had mixed results. Some show that stretching helps. Other studies show that stretching before or after exercise has little to no benefit.
Some research shows that stretching doesn’t reduce muscle soreness after exercise, and other studies show that static stretching performed immediately before a sprint event may slightly worsen performance.
Stretching can help improve flexibility, and, consequently, range of motion about your joints. Better flexibility may:
- Improve your performance in physical activities
- Decrease your risk of injuries
- Help your joints move through their full range of motion
- Enable your muscles to work most effectively
Stretching also increases blood flow to the muscle. You may learn to enjoy the ritual of stretching before or after hitting the trail, ballet floor or soccer field.
Before you plunge into stretching, make sure you do it safely and effectively. While you can stretch anytime, anywhere, be sure to use proper technique. Stretching incorrectly can actually do more harm than good.
Use these tips to keep stretching safe:
- Don’t consider stretching a warmup. You may hurt yourself if you stretch cold muscles. Before stretching, warm up with light walking, jogging or biking at low intensity for five to 10 minutes. Even better, stretch after your workout when your muscles are warm. Consider skipping stretching before an intense activity, such as sprinting or track and field activities. Some research suggests that pre-event stretching may actually decrease performance. Research has also shown that stretching immediately before an event weakens hamstring strength. Instead of static stretching, try performing a “dynamic warmup.” A dynamic warm-up involves performing movements similar to those in your sport or physical activity at a low level, then gradually increasing the speed and intensity as you warm up.
- Strive for symmetry. Everyone’s genetics for flexibility are a bit different. Rather than striving for the flexibility of a dancer or gymnast, focus on having equal flexibility side to side (especially if you have a history of a previous injury). Flexibility that is not equal on both sides may be a risk factor for injury.
- Focus on major muscle groups. Concentrate your stretches on major muscle groups such as your calves, thighs, hips, lower back, neck and shoulders. Make sure that you stretch both sides. Also stretch muscles and joints that you routinely use.
- Don’t bounce. Stretch in a smooth movement, without bouncing. Bouncing as you stretch can injure your muscle and actually contribute to muscle tightness.
- Hold your stretch. Breathe normally and hold each stretch for about 30 seconds; in problem areas, you may need to hold for around 60 seconds.
- Don’t aim for pain. Expect to feel tension while you’re stretching, not pain. If it hurts, you’ve pushed too far. Back off to the point where you don’t feel any pain, then hold the stretch.
- Make stretches sport specific. Some evidence suggests that it’s helpful to do stretches involving the muscles used most in your sport or activity. If you play soccer, for instance, stretch your hamstrings as you’re more vulnerable to hamstring strains. So opt for stretches that help your hamstrings.
- Keep up with your stretching. Stretching can be time-consuming. But you can achieve the most benefits by stretching regularly, at least two to three times a week. Skipping regular stretching means you risk losing the potential benefits. For instance, if stretching helped you increase your range of motion, your range of motion may decrease again if you stop stretching.
- Bring movement into your stretching. Gentle movements, such as those in tai chi or yoga, can help you be more flexible in specific movements. These types of exercises can also help reduce falls in seniors.
Remember the “dynamic warmup:” If you’re going to perform a specific activity, such as a kick in martial arts or kicking a soccer ball, start out slowly and at low intensity to get your muscles used to it. Then speed up gradually.
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