Effects of strength training on cardiovascular responses during a submaximal walk and a weight-loaded walking test in older females.

PURPOSE

The purpose of this study was to examine the effects of a total body strength training program on oxygen uptake (VO2), heart rate (HR), systolic blood pressure (SBP), and rate pressure product (RPP) during a submaximal walk and a weight-loaded walking test in healthy women 60-77 years old.

METHODS

The submaximal walk (2 mph and 3.5% grade) took place during stage 3 of a graded exercise test. The weight-loaded walking task consisted of treadmill walking at 2 mph while carrying a box weighing 40% of maximum isometric elbow flexion strength. The women strength trained three times per week for approximately 1 hour per session for 16 weeks.

RESULTS

Paired t tests determined that strength increased by 57% on six isotonic strength tests (one repetition maximum) and by 29% on two isometric strength tests. A repeated measures analysis of variance (ANOVA) was used to determine the pre- to post-differences between and within the two tests (alpha = 0.05). There was no change in VO2 but HR, SBP, and RPP decreased significantly during the submaximal walk and the weight-loaded walking test. However, average HR (135 to 120 bpm) and RPP (23.3 x 10(3) to 19.3 x 10(3)) decreased more during the weight-loaded walking test than during the submaximal walk (HR: 108 to 104 bpm; RPP 18.3 x 10(3) to 17.0 x 10(3)).

CONCLUSIONS

In conclusion, the reduced HR, SBP, and RPP indicates that strength training may reduce cardiovascular stress during daily tasks in healthy older women.