Physiological responses of individuals with Cerebral Palsy to Racerunning training

Regular exercise can confer numerous health and fitness benefits in individuals with Cerebral Palsy (CP). However, few exercise opportunities exist for people with CP, and the condition often leads to an inactive lifestyle. Consequently, people with CP have an increased risk of developing conditions including cardiovascular disease and type 2 diabetes (Balemans et al., 2013, Medicine and Science in Sports and Exercise, 45, 561-568). Inactivity also leads to muscular deconditioning which exacerbates CP symptoms (Riner & Sellhorst, 2013, Journal of Sport and Health Science, 2, 12-20). Racerunning (RR) is an activity for people with CP employing a pedal-less trike that supports the upper body and trunk, enabling propulsion using the legs. There is limited data on the physiological responses to RR. The aim of this study was to investigate the physiological and metabolic responses to habitual RR training in individuals with CP. Following institutional ethical approval, five participants (age 18 ± 4 years, height 1.61 ± 0.09 m, body mass 49.0 ± 12.5 kg, RR experience 5 ± 1 years, Gross Motor Function Classification Score 3.6 ± 0.9) (mean ± s) performed three habitual training sessions comprising a 2 mile run and 2 x 100 m sprints (session 1), 6 x 200m sprints (session 2) and 5 x 100m sprints (session 3). Percentage of age predicted heart rate maximum (HRmax) and GPS derived running velocity quantified training responses. Online gas analysis measured metabolic responses for 10 min pre- and post-training in session 3. Average session intensity was 75.3 ± 8.9%, 69.0 ± 15.3%, and 66.0% HRmax (one participant only) for sessions 1-3, respectively. The 2 mile run was completed in 19.6 ± 6.1 min at a mean intensity of 85.6 ± 7.9% HRmax and velocity of 9.8 ± 3.8 km.h. Peak intensity during session 2 sprints was 94.9 ± 7.9% HRmax, dropping to 71.0 ± 12.5% HRmax in the recovery periods. Mean sprinting velocity was 9.9 ± 1.9 km.h. Resting VO2 prior to session 3 was 0.30 ± 0.05 L.min and respiratory exchange ratio (RER) was 1.04 ± 0.04. Post-training, VO2 was 0.37 ± 0.05 L.min and RER 0.96 ± 0.06. Individuals with CP are able to perform activities at a sufficient intensity to promote health and fitness adaptations. Racerunning appears to provide an opportunity for appropriately intense physical activity in individuals with CP.