Blood pressure responses to a progressive step test in normotensive males and females

Structured exercise improves physical functioning in women with stages I and II breast cancer: results of a randomized controlled trial

PURPOSE

Self-directed and supervised exercise were compared with usual care in a clinical trial designed to evaluate the effect of structured exercise on physical functioning and other dimensions of health-related quality of life in women with stages I and II breast cancer.

PATIENTS AND METHODS

One hundred twenty-three women with stages I and II breast cancer completed baseline evaluations of generic and disease- and site-specific health-related quality of life, aerobic capacity, and body weight. Participants were randomly allocated to one of three intervention groups: usual care (control group), self-directed exercise, or supervised exercise. Quality of life, aerobic capacity, and body weight measures were repeated at 26 weeks. The primary outcome was the change in the Short Form-36 physical functioning scale between baseline and 26 weeks.

RESULTS

Physical functioning in the control group decreased by 4.1 points, whereas it increased by 5.7 points and 2.2 points in the self-directed and supervised exercise groups, respectively (P =.04). Post hoc analysis showed a moderately large (and clinically important) difference between the self-directed and control groups (9.8 points; P =.01) and a more modest difference between the supervised and control groups (6.3 points; P =.09). No significant differences between groups were observed for changes in quality of life scores. In a secondary analysis of participants stratified by type of adjuvant therapy, supervised exercise improved aerobic capacity (+3.5 mL/kg/min; P =.01) and reduced body weight (-4.8 kg; P <.05) compared with usual care only in participants not receiving chemotherapy.

CONCLUSION

Physical exercise can blunt some of the negative side effects of breast cancer treatment, including reduced physical functioning. Self-directed exercise is an effective way to improve physical functioning compared with usual care. In participants not receiving chemotherapy, supervised exercise may increase aerobic capacity and reduce body weight compared with usual care.

Urban angina in the mountains: effects of carbon monoxide and mild hypoxemia on subjects with chronic stable angina

Seventeen men with stable angina pectoris who resided at or near sea level performed cardiopulmonary exercise stress tests after they were exposed to either carbon monoxide (3.9%), carboxyhemoglobin, or clean air. Investigators conducted the tests at sea level, and they simulated 2.1-km altitudes (i.e., reduced arterial oxygen saturation by approximately 4%) in a randomized double-blind experiment in which each subject acted as his or her own control. The duration of symptom-limited exercise, heart rate, indicators of cardiac ischemia and arrhythmia, blood pressure, and respiratory gas exchange were measured. Analyses of variance showed that both independent variables-altitude and carbon monoxide-significantly (p < or = .01) reduced total duration of exercise for the group as a whole (n=17) and reduced the time to onset of angina for a subset of 13 subjects who experienced angina during all four test conditions (p < .05). Time to onset of angina was reduced either after exposure to sea-level carbon monoxide (9%) or to simulated high-altitude clean-air exposures (11%), compared with clean air at sea level. Joint exposure to carbon monoxide at a simulated high altitude reduced the time to onset of angina, relative to clean air, by 18% (p < .05). Other cardiological, hemodynamic, and respiratory physiological parameters were also affected adversely by altitude and carbon monoxide exposures. None of the parameters measured were associated significantly with either altitude or carbon monoxide, indicating that the effects of carbon-monoxide-induced and high-altitude-induced hypoxia were additive. The results of this study suggest that high-altitude conditions exacerbate the effects of carbon monoxide exposures in unacclimatized individuals who have coronary artery disease.