CARDIOVASCULAR AND MUSCULAR ADAPTATIONS TO COMBINED ENDURANCE AND STRENGTH TRAINING IN ELDERLY WOMEN

Twenty-one women aged 60-75 years were examined to determine whether c ombined endurance and strength training resulted in greater increase i n peak oxygen consumption, sub-maximal time to fatigue, cardiac output , stroke volume, and leg extension load when compared to endurance tra ining alone. Subjects in both the endurance training (E) and endurance and strength (E & S) groups trained 3 days a week, for 12 weeks, at a n intensity of 70-80% (V) over dot O-2 peak for 30 min on a cycle ergo meter. Subjects in the E & S groups also used resistance equipment to train the knee extensors. The workload for resistance training was bas ed on an initial assessment of 10 repetitions maximum (10 RM), with 80 % of that value used for training, three times weekly. Peak oxygen con sumption increased to an average of 24.8 and 29.9% in the E arid E & S groups, respectively, with no difference between groups. Subjects in the E & S and E groups significantly increased sub-maximal endurance t ime by 396 and 165%, respectively. Cardiac output, stroke volume, and arteriovenous oxygen difference at 80% peak (V) over dot O-2 were unch anged by either of the training methods. A needle biopsy was taken fro m the vastus lateralis before and after 12 weeks of training. Chi-squa re analysis of fibre area data showed an increase in the frequency of larger type I fibres-in the post-training data from the E & S group, b ut an increase in the frequency of smaller fibres in the E group post- training; however, mean fibre area was not significantly changed by tr aining. These data suggest that greater improvements in sub-maximal ti me to fatigue and strength is achieved when resistance training is add ed to an aerobic training programme in healthy elderly women.