RESISTANCE AND AEROBIC TRAINING IN OLDER MEN - EFFECTS ON VO2PEAK ANDTHE CAPILLARY SUPPLY TO SKELETAL-MUSCLE

Both aerobic training (AT) and resistance training (RT) may increase a erobic power (VO2peak) in the older population; however, the role of c hanges in the capillary supply in this response has not been evaluated . Twenty healthy men (age 65-74 yr) engaged in either 9 wk of lower bo dy RT followed by 9 wk of AT on a cycle ergometer (RT-AT group) or 18 wk of AT on a cycle ergometer (AT-AT group). RT was performed three ti mes per week and consisted of three sets of four exercises at 6-12 rep etitions maximum. AT was performed three times per week for 30 min at 60-70% heart rate reserve. VO2peak was increased after both RT and AT (P < 0.05). Biopsies (vastus lateralis) revealed that the number of ca pillaries per fiber perimeter length was increased after both AT and R T (P < 0.05), paralleling the changes in VO2peak, whereas capillary de nsity was increased only after AT (P < 0.01). These results, and the f inding of a significant correlation between the change in capillary su pply and VO2peak (r = 0.52), suggest the possibility that similar mech anisms may be involved in the increase of VO2peak after high-intensity RT and AT in the older population.