Aerobic exercise safely increases endurance in heart failure patients:
Researchers from the European Heart Failure Training Group found benefits of physical rehabilitation in 134 patients (mean age 60 years, 94% male) with chronic heart failure (HF). The extent of heart failure among the patients, using the New York Heart Association Functional Classification system, was II (50%) and III (48%). For 6 to 16 weeks, study participants followed one of two exercise regimens: cycle ergometry (20 minutes 4-5 times per week at an intensity of 70%-80% of a predetermined peak heart rate) or cycle ergomertry combined with calisthenics or body weight exercises (5 days/week with stationary running). Cycle ergomertry warm up and cool down lasted for 1-3 min at 25 W. At the end of the study, improvement in resting catecholamines and hormones (such as epinephrine and norepinephrine) and heart rate variability were associated with a 13% increase in oxygen consumption (VO2) and a 17% increase in exercise duration. Compared to the cycle ergometry alone patients, the 54 patients on a combined exercise regimen achieved significantly better VO2 (2.7 vs 1.2 ml.kg.min-1). VO2 was also found to be linked to the duration of the program; after 16 weeks training VO2 was significantly higher than after 6 weeks (2.6 vs 0.3 ml.kg.min-1). No significant side effects were reported. (12)