Physical Conditioning of Sedentary Young Men with Ankle Weights during Working Hours

Abstract

An intact work crew of nine weather observers (ages 19-32 y) wore weighted ankle spats for 20 continuous days for 7·5-7·9 h each day on the job while performing normal duties and for an equal amount of time on days off. Four observers continued wear for another 20 days. Weights on each ankle were 2·25 kg for two days and 3·0 kg thereafter. Oxygen uptake (V˙_O2) and heart rate (HR) were determined before and after conditioning at six submaximal work loads: level walking at 1·12 and 1·56ms⁻¹, with and without ankle weights, and crgometer cycling at two work loads selected to elicit final HR near 150 and 180 beat min⁻¹. Submaximal HR declined and predicted aerobic power at HR = 180 (PAP₁₈₀) increased throughout the conditioning period, but significance was reached only after six weeks (mean HR decrease = 18 beat min⁻¹, p<0·05; mean PAP₁₈₀ increase = 0·15 mmolmin⁻¹ kg⁻¹, p<0·05). After three weeks without weights, both improvements partially decayed. V˙_O2 and HR were obtained on the job from three subjects who had trained for six weeks. Although HR increased an average of 12 beat min⁻¹ when ankle weights were worn, the observed cardiovascular training stimulus remained quite low, averaging 98 beat min⁻¹. This on-the-job conditioning method appears useful to sedentary individuals as a preliminary to more strenuous activity.