Performance and exertional variations during walking, running and jumping on terrains of varying compliance

Abstract

This paper reviews three coordinated studies that investigated the effects of terrains of varying compliance (sand and a hard surface) during walking, running and jumping. The compliance of sand for each research objective was not significantly different and was verified by measurements using a rapid cone penetrometer. Walking on sand: Fourteen adult males participated with a mean age of 34.6 years, who were 72.6 kg in mass, and 172.5 cm in stature. They walked at 3, 4, 5, 6 and 7 km.hr-1 on sand and grass surfaces. Physiological measures included heart rate, O2 uptake, CO2 exhalation, ventilation (VE), and relative oxygen uptake. Results indicated that there was a significant increase (p<0.01) in all physiological indices when walking on sand compared to grass at 3 to 7 km.hr-1, with the greatest disparity between the surfaces (ratio=1.63) in relative oxygen uptake at 5 km.hr-1. Running on sand: Twenty adult male participants with a mean age of 27.7 years, who were 78.3 kg in mass, 179.1 cm in stature and 13.1% body fat. The Multi-Stage Fitness Test (MSFT) was the running protocol used on sand and grass surfaces. Two responses were evaluated namely heart rate and Ratings of Perceived Exertion. There was a significant (p<0.05) elevation in heart rate response by approximately 9% and an increased RPE of 17% when running on sand, and this resulted in an overall mean performance decrement of 37.3% in terms of MSFT shuttles (distance) completed. Jumping on sand: Forty one male participants with a mean age of 20.4 years, who were 79.56 kg in mass, 178.03 in stature and 12.6% body fat. The mean vertical jump performance (VJP) achieved on sand was 49.0 cm, compared to 55.11 cm on a hard surface. The mean VJP on sand was 11.03% less than that achieved on a hard surface, which was significantly (p<0.01) less. Conclusion: Sand appears to have a distinctive and significant effect on human performance during walking, running and jumping when compared to the same action performed on a hard (non-compliant) surface. Walking on sand increases physiological demand by as much as 63%, while running a predictive test of aerobic capacity (MSFT) resulted in a 37.3% decrease in distance-shuttles completed. Jumping on sand resulted in a mean 11.03% loss in performance compared to the same action on a hard surface.