Effects of plyometric exercises on muscle-activation strategies and response-capacity to balance threats in children with hemiplegic cerebral palsy

ABSTRACT

Objective

Children with hemiplegic cerebral palsy (hCP) experience a disorganized muscle activation pattern that adversely affect their ability to respond to balance perturbations. This study examined the effect of plyometric exercises on muscle-activation strategies and response-capacity to balance threats in children with hCP.

Methods

In a pre-, posttest control-group study, 34 children with hCP were allocated randomly to either the control group (n = 17; received a traditional physical rehabilitation program, lasted for 45 minutes/session, twice/week for three successive months) or the plyometric group (n = 17; received a progressive plyometric training program in three blocks, twice/week over three months plus the traditional physical rehabilitation). Quadriceps/hamstring co-contraction ratio (Q/H Co-CR) and response-capacity to balance threats were assessed pre- and post-treatment.

Results

Post-treatment, the Q/H Co-CR and balance control improved significantly in the control (P = .03, P = .0003 respectively) and plyomteric group (P = .001, P ˂ 0.001 respectively). However, the plyometric group showed better improvements in Q/H Co-CR (P = .0001) and balance control (P = .027) when compared to the control group.

Conclusion

Incorporation of plyometric exercises into traditional physical rehabilitation could improve muscle-activation strategies and enhance balance control in children with hCP.

KEYWORDS:

• Cerebral palsy
• strength training
• stretch-shortening cycle exercises
• electromyography
• balance control