Knee wraps may help you to use heavier weights for squats and leg presses in the gym, but regular use might not be such a good idea. According to British sports scientists, knee wraps alter how you move during a squat in such a way that you’re likely to cause more damage to your knee joints.
If you use knee wraps during strength training you can generate more power in your lower body. This has been officially known since 1990 [J Strength Cond Res 12: 30–35, 1990.], but long before this strength athletes had worked out that they could do heavier squats by using the things. It’s probably the elasticity of the material that helps.
Little was known however about the effect of wearing knee wraps on how you carry out a squat. That’s why sports scientists at the University of Chichester got 10 experienced male strength athletes to perform squats with [Wrapped] and without knee wraps [Unwrapped].
They discovered that there was a pronounced effect on how the movement is performed. During a squat the weight on your shoulder not only makes a vertical movement, but also a horizontal one. Wearing wraps reduced the horizontal movement considerably, the researchers observed.
As the weight was lowered [from a to b] the horizontal component of the movement decreased by 39 percent; as the weight was raised [from c to d] the horizontal movement decreased by a massive 99 percent.
As a result of the reduction in horizontal movement, the researchers suspect that friction in the knee joint increases, leading to more wear and tear.
This effect is reinforced because the knee wraps help the athletes to perform the movement faster: power increases.
“We therefore propose that knee wraps should not be worn during the strength and conditioning process and that if an athlete feels that additional support is needed for the knee, the integrity of the joint is thoroughly assessed and treated rather than relying on artificial aid that could exacerbate any underlying issues”, the researchers write.
Charles Poliquin agrees with the British researchers’ view of the matter. [charlespoliquin.com December 30, 2011] He also fears that strength athletes who always train their legs using knee wraps do not develop their hip muscles sufficiently.
Wearing knee wraps affects mechanical output and performance characteristics of back squat exercise.
Lake JP, Carden PJ, Shorter KA.
Source
Department of Sport and Exercise Sciences, University of Chichester, Chichester, United Kingdom. j.lake@chi.ac.uk
Abstract
The aim of this study was to investigate the effects of wearing knee wraps on mechanical output and performance characteristics of back squat exercise. Ten resistance trained men (back squat 1 repetition maximum [1RM]: 160.5 ± 18.4 kg) performed 6 single back squats with 80% 1RM, 3 wearing knee wraps, 3 without. Mechanical output was obtained from ground reaction force, performance characteristics from digitized motion footage obtained from a single high-speed digital camera. Wearing knee wraps led to a 39% reduction (0.09 compared with 0.11 m, p = 0.037) in horizontal barbell displacement that continued during the lifting phase. Lowering phase vertical impulse remained within 1% across conditions; however, the lowering phase was performed 45% faster (1.13 compared with 1.57 seconds). This demonstrated that vertical force applied to the center of mass during the lowering phase was considerably larger and was likely a consequence of the generation and storage of elastic energy within the knee wrap. Subsequent vertical impulse applied to the center of mass was 10% greater (192 compared with 169 N·s, p = 0.018). Mechanical work involved in vertically displacing the center of mass was performed 20% faster and was reflected by a 10% increase in peak power (2,121 compared with 1,841 W, p = 0.019). The elastic properties of knee wraps increased mechanical output but altered back squat technique in a way that is likely to alter the musculature targeted by the exercise and possibly compromise the integrity of the knee joint. Knee wraps should not be worn during the strength and condition process, and perceived weakness in the knee joint should be assessed and treated.
PMID: 22995993 [PubMed – indexed for MEDLINE]
Source: http://www.ncbi.nlm.nih.gov/pubmed/22995993
Avoid Wearing Knee Wraps When Squatting For Better Strength Development
Avoid wearing knee wraps when squatting for better, more complete strength development. Knee wraps are commonly worn by powerlifters and occasionally by athletes and trainees, but they should be avoided. Knee wraps are worn because they increase the amount of maximal weight that can be lifted by increasing the speed with which the lift is performed and storing elastic energy in the wrap. But new research shows they compromise the training of the hip musculature, which can have a negative effect on the integrity of the knee making it critical that athletes avoid them.
The study, published in the Journal of Strength and Conditioning Research, compared mechanical output and performance characteristics of squats performed with and without knee wraps at 80 percent of the 1 RM. Trained college-age men were used and they performed three single repetitions of a back squat. The knee wraps provided a mechanical advantage, which was represented by the fact that the reps performed with wraps were completed faster. This resulted in a very high amount of elastic energy to be stored in the wraps during the down phase of the squat. That energy is then released during the up phase, resulting in greater peak power output and is the reason more weight can be lifted with wraps.
There was also a large reduction in horizontal displacement of the barbell when knee wraps were worn; indicating that the participants’ traditional squat form was changed dramatically and different muscles were used. The knee wraps led to a restricted motion around the hip joint, which caused a more upright posture and forced greater flexion at the knee joint. The restricted motion meant that the powerful hip flexors and extensors were not activated to the same extent as in a normal squat, putting trainees at greater risk of injury and underdevelopment of these muscles. This could result in compromised integrity of the knee joint.
Another possible effect of knee wraps is the development of osteoarthritis and tendinitis. One study found that elite powerlifters had a 31 percent incidence of osteoarthritis of the knee compared to runners who had only a 14 percent incidence. Researchers suggest that although knee wraps are frequently worn to protect the knee joint, this may in fact increase the friction between the patella and the underlying cartilage because the wraps compress the knee cap into the thighbone, increasing the risk of injury and knee pathologies such as arthritis.
Take note that one reason given for wearing knee wraps besides the greater amount of weight that can be lifted is that they keep the knee warm, which increases the synovial fluid present, better lubricating them. Instead of wearing knee wraps you can get neoprene knee pads to keep the knee warm that do not alter movement mechanics or affect the amount of weight lifted. Unless you are a powerlifter, avoid using knee wraps and you will have a more balanced, stronger lower body.
References:
Lake, J., Carden, P., et al. Wearing Knee Wraps Affects Mechanical Output and Performance Characteristics of Back Squat Exercise. Journal of Strength and Conditioning Research. December 2011. Published Ahead of Print.
Bogduk, N., Twomey, L. Clinical Anatomy of the Lumbar Spine. New York: Churchill Livingstone. 1991.
Baechle, T.R., ed. Essentials of Strength Training and Conditioning. Champaign, IL: Human Kinetics. 1994.
