Treating injuries commonly associated with aerobics
Dr Geoff Davies looks at the injuries your patients keen on aerobics may present and how they might be prevented
erobic dance involves the movement of large muscle groups in continuous rhythmic activity to music. Aerobics originated in the late 1960s but became very popular in the UK in the late 1980s and is currently one of the world's most popular ways to get fit and stay fit.
Although there are many different types of aerobics it is essentially an hour's workout set to music. A typical programme begins with five to 10 minutes of warm-ups and stretching, peaks with 30 minutes of target heart range dance and can include 20 minutes of a muscle-stretching floor programme known as body sculpting, and ends with five to 10 minutes of cool-down with more stretching.
During aerobics, the body is in motion through space and either both feet lose contact with the ground (high impact) or at least one foot is in contact at all times (low impact). There are more then a dozen aerobic dance variants, many of which are extensions or combinations of high and low impact.
What injuries occur?
Aerobics can be associated with a significant number of sports injuries. A study in 1995 determined the incidence of injury in aerobics classes in Perth which found 35 per cent of instructors and 22 per cent of participants reported at least one injury caused or aggravated by aerobics over a 12-month period. When hours of participation or instruction per year were considered, the injury incidence rate was 0.18 injuries per 100 hours for the instructors and 0.27 injuries per 100 hours for the participants.
Instructors reported ankle or foot injuries (43.3 per cent) and shin injuries (23.3 per cent) most commonly while participants reported that the knee was most commonly injured (particularly in step classes)1.
In 1993, the American Journal of Sports Medicine reported the injury rates of different sports2. Rugby was one of the highest with a rate of 30 injuries per 1,000 hours of activity, while aerobics had a rate of five which was equivalent to the injury rate in tennis.
Injuries in aerobics, as in many sports, can be divided into two categories, traumatic and overuse injuries. Both are relatively common in aerobics.
Traumatic injuries arise as a result of a fall, twist or similar accident and most commonly involve the ankle and knee. Management of these injuries is well documented and beyond the remit of this article.
Overuse injuries arise gradually, usually as a result of a change in the amount or intensity of aerobics, or some other training errors. Shin pain is the most common overuse injury, while foot and knee overuse injuries are also common.
· Plantar fascitis. This debilitating condition can often occur in aerobics. It is a form of overuse injury often precipitated by forefoot and rearfoot instability which causes excessive pronation of the foot which stresses the origin of the plantar fascia on the calcaneus. A very painful heel is the end result which often causes long-term debility. Treatment revolves around correcting any biomechanical precipitating triggers like hyperpronation. Consideration of orthotics to correct such gait abnormality can prove curative. Carefully placed cortisone injections can be of value but are best reserved for the more intractable cases because of the significant risk of rupture of the plantar fascia.
· Shin pain. This can occur due to a variety of pathological processes producing differing clinical entities, for example medial tibial periostitis, compartment syndrome and stress fractures. A detailed history will often clinch the diagnosis. Treatment will involve correcting any foot biomechanical problems possibly with orthotics, along with appropriate muscle stretching and strengthening regimes.
· Achilles tendonosis. Because of the frequent plantar flexion involved in aerobics, calf and Achilles pain can be quite common. Often stretching a tight Achilles can remedy the situation, so this along with calf muscle strengthening is important in rehabilitation of such injuries. Appropriate footwear is also important to reduce the risk of this problem recurring.
· Stress fractures. More common in aerobic instructors and especially females. Causes include poor footwear and hard surfaces combined with overuse. These injuries often occur in the metatarsals. X-rays or bone scans may be needed to clinch the diagnosis. Treatment involves relative rest, correction of any biomechanical errors, followed by a gradual rehabilitation after symptoms have settled. Any training errors need to be identified to minimise the risk of a future recurrence.
· Anterior knee pain. This is quite a common problem in aerobics because of the repetitive movements, particularly involving flexion and extension of the leg. Overuse problems are the major type. Ensuring good quadriceps strength, particularly the vastus medialis obliqus (VMO), will help to ensure good patella tracking, helping to minimise anterior knee pain. Relative rest with quadriceps strengthening then gradual rehabilitation will enable a return to aerobics in most cases.
· Muscle strains. These can occur in the quadriceps, hamstrings and calf as well as the back and abdominal muscles. These often result from doing too much too soon, particularly in the beginner, or a generalised overuse injury. Generally these will settle down in a few days but can take several weeks to heal fully. Addressing any training errors will help to prevent a recurrence in the future but rest, stretching and muscle strengthening may all be needed to solve the problem. Physical modalities, including ultrasound and mobilisations, may improve symptoms and aid recovery.
· Low back pain. Most low back pain in aerobics is caused by weak, inflexible back muscles, often with coexisting weak abdominal muscles. Attention should be paid to improving core stability by strengthening both the lower back and abdominal muscles.
Prevention of injury
Several common factors can precipitate injury and must be addressed to reduce the
risk of injury:
· Appropriate footwear is essential to help avoid overuse injuries
· Exercising on appropriate surfaces
· Remember to warm up properly before a class
· Pre-exercise stretching has not been shown to reduce the injury rate3 but does improve
overall flexibility, which can be beneficial
· Foot biomechanics often play a large part in overuse injuries of the lower limb, and their correction with orthotic devices is often very helpful.
Aerobics has an injury rate equivalent to tennis~
Treatment of acute injuries
Remember P. R. I. C. E.
Protection from further injury
Compression of injury site if appropriate
Elevate the affected area if possible
Address underlying causes and correct if possible (for example, appropriate footwear, appropriate frequency of participation), correct any obvious biomechanical abnormalities if these are felt to be contributory (for example, hyperpronation with orthotics).