Adaptations to endurance training in the healthy elderly: arm cranking versus leg cycling

The effects in healthy elderly subjects of cycle ergometer or arm ergometer training on peak oxygen consumption (VO2peak) and ventilatory threshold (VT) were studied. The aim was to determine the benefit of each training modality on specific and cross exercise capacity. The cross-effect was also evaluated as an index of the central nature of the adaptive response to training. Eighteen non-smoking healthy males (age: 69 ± 5 yr; body mass: 77 ± 8 kg) were randomly assigned to three groups, performing an arm cranking (ARM) or a cycloergometer (CYC) training (12-week, 30 min, 3 times/week) or no training (control, C). Before and after the training period, subjects performed an incremental test to exhaustion both on the ergometer on which they trained (specific test) and on the other ergometer (cross test). Respiratory variables were measured breath by breath and heart rate (HR) was recorded. Peak oxygen consumption (VO2peak), ventilation (VEpeak), oxygen pulse (O2Ppeak) and heart rate (HRpeak) was averaged over the last 10s of exercise. Following training, while HRpeak remained unchanged, significantly higher Wpeak, VO2peak, VEpeak and O2Ppeak were obtained in both training groups, on both ergometers. The amplitude of the increase in Wpeak, VO2peak and O2Ppeak was significantly higher for specific than for cross tests (~19% vs. ~8 % in CYC; ~22% vs. ~9% in ARM, p<0.01) while the increase in same test condition was similar. No change was observed in the C group. The results indicate that aerobic training brought about with different muscle masses, produce similar improvements in maximal and submaximal exercise capacity. Roughly half of such improvements are specific to exercise mode, which reveals peripheral adaptations to training. The other half is non-specific since it influences also the alternative exercise modality, and is probably due to central adaptations.