In patients with COPD, upper limb solicitation was important in daily activity. However, very few studies concerning upper limb physiological adaptation during exercise was available. The purpose of this study was to assess and compare the upper limb and lower limb capacities in severe COPD patients during incremental and constant load exercises.
Ten COPD patients with homogenous age and severe air flow limitation (age 65 ± 6.1 [SD]yr; FEV1: 35% ± 5% predicted) and ten healthy control (age 63 ± 5.3 [SD]yr; FEV1: 102 ± 4% predicted) subjects were studied.
at peak exercise, maximal values of load, VO2, RER, VE, and HR were significantly lower in patient with COPD, compared with healthy controls for both conditions(p<0.001). On the opposite, no significant difference was observed between arm and leg for these parameters in COPD patients. For both conditions (arm vs. leg), mechanical efficiency (ME) was significantly lower in patients with COPD than in control subjects (20.97 % ± 2.33 % and 25.90 % ± 3.30 % for arm; 20.91 % ± 2.92 % and 27.38 % ± 3.03 % for leg, p< 0.001). In both populations, ME of the lower limb was comparable to that of the upper limb. In COPD patients within homogenous and sever air flow limitation, during upper-limb exercise, as observed in previous study, we noted that exercise capacity was relatively more preserved than during leg exercise.
To explain this situation, we hypothesized that a part of the upper limb mass muscle is relatively less deconditioned compared to lower limb and could explain why maximal workload values are relatively well preserved during arm exercise. Furthermore, it’s seems to be possible that a level of exercise was reached beyond which the VO2 could not be increased.
improvements in upper-limb strength or endurance resulting from training could lead to improved overall functional capacity and ability to perform activities of daily living.
Data at Peak Exercise.Arm CrankLeg CycleControlsCOPDControlsCOPDPMA, watts94±12.65†54±8.54*162±21.5058±10.33*V;\S\UP6(˙O2, ml.min-1.1597±168.†1054±67*2190±2711109±116*RER1.15±0.041.09±0.03*1.14±0.051.08±0.03*V;\S\UP6(˙E, l.min-1.61.8±6.2†28.9±3.21*77.2±9.5331.6±4.06*V;\S\UP6(˙E / MVV, %60.2±4.8†88.6±1.6*74.9±5.895±2.1*VT, l.1.64±0.13†0.92±0.18*1.95±0.230.98±0.17*fb, breaths min-1.37.8±2.9†31.5±3.4*39.8±3.3432.5±3.3*HR, beats min-1.156±5.7117±6*157±5.1125±8.8*
Table 2:Values are means ± SE; V;\S\UP6(˙O2, O2 consumption; V;\S\UP6(˙CO2, CO2 excretion; RER, respiratory exchange ratio; V;\S\UP6(˙E, minute ventilation; MVV, maximal voluntary ventilation; VT, tidal volume; fb, frequency of breathing; HR, heart rate;†
p<0.05 arm vs leg;*
p<0.05 COPD patients vs control.
Castagna Olivier, None.