Implementation of Calf Endurance Training in a Touring Group of Professional Circus Performers: A Feasibility Study

BACKGROUND: Demanding performance schedules in modern professional circus can result in less time for injury rehabilitation and strength and conditioning for injury prevention. Lower limb injuries are a common injury presentation in Cirque du Soleil touring show performers. OBJECTIVE: To examine the feasibility of introducing a calf raise exercise program in an established professional touring circus show over a 9-week period. METHODS: Twenty-nine professional Cirque du Soleil circus performers were recruited (mean age 31.28 [SD 4.99] yrs). Performers completed the Oslo Sports Trauma Research Centre Overuse (OSTRC) questionnaire each week for 18 weeks. In the second 9-week period, performers completed one set of single-leg calf raises to fatigue on each limb, once per day, every workday. Health problems between each 9-week period were compared. Feasibility was measured via program adherence and an end-of-study survey. Calf endurance was assessed by measuring the number of single leg calf raises to fatigue. RESULTS: Adherence was high throughout the program, with 93.5% of all exercise sessions completed. Endurance increased by a mean of 22.62 (SD 27.99) calf raises. No significant changes in the prevalence of self-reported soreness and injury were found: 51.9 (95%CI 44.4, 57.5) of the population reported lower limb injuries during the pre-intervention period and 52.5 (95%CI 49.2, 55.8) during the intervention. Similarly, no significant changes were found in severity scores: 20.7 (95%CI 17.7, 23.7) pre-intervention and 20.9 (95%CI 19.4, 22.4) during intervention. CONCLUSION: A single-leg calf raise exercise program can be feasibly introduced into a touring, performing professional circus show without increasing injury numbers or self-reported soreness. Furthermore, gains in calf raise endurance can be obtained during a 9-week intervention period.