Exercise as it relates to Disease/Effectiveness of resistance training among people with cerebral palsy

What is cerebral palsy?
Cerebral Palsy is a term used to describe a number of disorders leading to deficits in neural and postural control caused by damage to the brain during pregnancy or soon after birth.

Prevalence and incidence
Cerebral palsy affects approximately 34,000 Australians. A child born in Australia that is either diagnosed or will develop cerebral palsy is estimated to occur once every 18 hours.

Problems associated with cerebral palsy
Due to the effect cerebral palsy has on individuals motor function and coordination, it results in difficulties with many activities including walking without aids, running, negotiating steps and moving safely over uneven ground. This leads to children having a reduced participation in school, leisure and social events whilst also leading to negative psychological implications that include low confidence and self-esteem. Although cerebral palsy is non-progressive the neutral decline associated with ageing leads to a further decrease in mobility towards later age, leading to gross negative effects on older adult such as a lack of independence. Many reduce their amounts of physical activity and some may even stop walking due to an increased incidence of falls, leading to an risk of other diseases such as obesity and cardiovascular disease.

What is resistance training?
Resistance training is a method of physical training that involves the use of body weight, free weights, resistive bands and other tools in order to increase muscular strength and endurance. Resistance training can be broken down into different types based on how the exercise engages the muscle, shown below.

Previous view on resistance training and cerebral palsy
Resistance training was avoided as a treatment for both children and adults diagnosed with cerebral palsy as it was though that excessive effort from the muscle would result in greater co-contraction and spasticity. This was based on the belief that the primary problem was agonist restraint rather than muscle weakness, with traditional treatments focussing on posture and co-contraction correction.

What are the benefits of resistance training?
Resistance training has numerous benefits depending on which muscle groups are targeted. As gait function is widely problematic across many forms of cerebral palsy most research and training has been focussed on increasing the strength within the lower extremities. After completing a resistance training program designed to increase strength in the major support muscles of the lower limbs young people displayed significant improvements in strength, flexibility and posture, with no negative results in terms of spasticity and co-contractions. This lead to improved walking function and the ability to negotiate steps and also carried positive behavioural influences with participants having increased levels of confidence and also engaging in more leisure and physical activities. These findings are supported by additional research that also displayed improved walking function with no negative effects after training. Children that completed a circuit training class that involved resistive exercises resulted in functional strength increases resulting in faster 10 metre walk times and increased stride lengths, with these improvements being retained at a follow-up 8 weeks after the cessation of training. Progressive resistance training also lead to improvements in muscular strength, walking speed and step rate that were retained at a 4 week follow up, whilst it has also been widely determined that muscle strengthening does not lead to increases spasticity and co-contractions as was previously thought. Adults also benefit greatly from resistance training programs with a deterioration of condition, muscle strength and balance control accounting for major reasons of decreased walking. After completing a progressive resistance training program focussed on the lower extremity adults had a significant improvements in strength, walking velocity and motor function with again, no change in spasticity. Older adults have also been known to enjoy the social aspect of the training program if it is conducted in a group setting, leading to increases in muscle strength leading to improved ability to perform everyday activities, such as walking, and also higher a participation in family, social and leisure activities.

Delivery of resistance training
The resistance training delivered to people with cerebral palsy are very similar for both adults and children. This includes exercises designed at increasing strength in the lower extremity using both body weight and adjustable added weights where participants complete 3 sets of 8-10 repetitions maximum in each set between 2-3 times each week over a 6-10 week period. In order to achieve the best results the program must be individualised to the participants specific needs which may vary greatly throughout a group, however there are clear advantages to conducting the training in a group setting. These include time efficient, economical form of delivering the therapy with group dynamics also having a positive effect on motivation and exercise performance in children, while the group setting benefitted older adults by increasing their enjoyment through social interaction which in turn has a positive influence on their adherence to the program.

Precautions
Resistance training has the potential to be harmful and cause injury if it not performed correctly, particularly in young populations, however when performed correctly the advantages are clearly evident. Supervision and clear instruction is needed to be given to the participants by their physiotherapist on how to correctly perform each exercise at the commencement of the program and also reassessed as the training progresses. This is more important where added weights are being used, where participants must not load weights greater than 70% of their 1 repetition maximum, and only the physiotherapist is able to make a judgment on when to increase weight. If you are considering undertaking a resistance based program it is imperative that you do not do so without first consulting with a physiotherapist and gaining the correct instruction before-hand, as it may be harmful resulting severe injuries.

Conclusion
Research clearly supports the increases in muscular strength, flexibility, balance, walking ability and motor ability gained by both children and adults with cerebral palsy after participating in resistance training programs. These improvements then have massive carryover effects into improving the individuals quality of life through methods such as increasing their confidence and ability to engage in more social and leisure activities they would not regularly do, whilst also allowing them to have a greater amount of independence by making it easier to perform many everyday tasks. Thus resistance training is an effective treatment for people suffering from cerebral palsy if it is performed correctly with the right guidance and supervision, with participants vastly improving their mobility that is still present at follow-up examinations, without any signs of increased levels of spasticity or co-contractions that such training was once believed to cause.