The effects of 8 wk of soft-sand (n = 19) and firm-surface walking (n = 19) on blood lipids, submaximal fitness (8-min walk at 4.5 km/hr), and leg strength in elderly (60+ yr), sedentary women were studied. Significant main time effects (p < .005) were found for blood lipids. The surface interaction effect for high-density lipoprotein approached significance (p = .052), with a tendency for higher levels in the sand group postintervention (p = .06). Neither group reported significant differences across time for submaximal oxygen consumption (p = .223), but a greater percentage reduction in heart-rate response to the 8-min walk was reported in the sand group (p = .016). Knee strength did not change in either group, whereas hip strength significantly improved in both groups (p = .0001), with larger effect sizes reported in the sand group. Overall, both groups showed improvements in blood lipids, fitness, and strength, with strength changes being slightly higher in the sand-walking group.
The authors are with the School of Sport Science, Exercise and Health, The University of Western Australia, Crawley, WA 6009 Australia.