Physiological responses to maximal treadmill and handweighted exercise

The purpose of this investigation was to compare the peak physiological responses among four protocols that employed different amounts of handweighted exercise in 16 males (aged 26.3 +/- 4.1 years). The four protocols were (a) uphill treadmill running (UR; 3.36 m.s-1, 2.5% grade increase-3 min-1); (b) uphill treadmill walking while pumping 1.36-kg handweights (HW) (UWHW; 1.79 m.s-1, 5.0% grade increase x 3 min-1; (c) treadmill walking while pumping .91-kg HW (WHW; 1.79 m.s-1, 0% grade, .91-kg HW increase x 3 min-1); and (d) standing in place and pumping HW (SHW; arm work as described in WHW). It was hypothesized that the peak responses would be inversely proportional to the estimated muscle mass activated (i.e., UR = UWHW > WHW > SHW). Dependent variables included peak oxygen uptake (VO2 peak), peak heart rate (HRpeak), peak ventilation (Ve peak), and peak respiratory exchange ratio (RERpeak). No differences were noted between UR and UWHW with respect to any of the dependent variables. All variables (except RERpeak) were greater (p < .01) in UR and UWHW than either WHW or SHW. RERpeak was greater (p < .01) in UR and UWHW than in WHW. VO2 peak and HRpeak were greater (p < .01) in WHW when compared to SHW. Mean VO2 peak was 97.5, 69.7, and 60% of UR for UWHW, WHW, and SHW, respectively. Therefore, walking and pumping handweights provides a maximal stimulus to the oxygen transport system.