[The clinical role of anaerobic threshold in physical training of patients with recent myocardial infarction].
Twenty-seven patients with recent myocardial infarction were studied to evaluate the clinical usefulness of the anaerobic threshold (AT) in physical training as cardiac rehabilitation at home. The 27 patients were divided into trained and control groups. Symptom-limited treadmill exercise tests were conducted before and six weeks after the prescribed aerobic training. Heart rate (HR), systolic blood pressure and respiratory gases (VO2, VCO2 and VE) were noninvasively measured throughout the exercise periods. AT was defined as systemic increase in the ventilatory equivalent O2 (VE/VO2) without an increase in the ventilatory CO2 (VE/VCO2) during the increasing work load. The patients in the trained group were obliged to perform aerobic walking training requiring 90-100% HR of the AT level for 30 min, four to six days per week. 1. In the trained group, exercise time, peak VO2, and AT on treadmill performance were significantly increased compared with those of the pre-training values. However, in the control group, these parameters were not significantly changed. A significant reduction in double products was observed during submaximal workload in the trained group. 2. Factors related to the training effects: The training effect expressed by delta peak VO2 correlated significantly with the initial peak VO2 (pre-training peak VO2) (y = 35.4 - 1.29x, r = 0.70), but there was no correlation between left ventricular function and delta peak VO2. These results indicated that aerobic exercise at home guided by the AT level is safe and beneficial for patients with recent myocardial infarction.
Tsuji
M
M
Second Department, Nihon University School of Medicine, Tokyo.
Saito
S
S
Ando
T
T
Moriuchi
M
M
Tamura
Y
Y
Tanigawa
N
N
Ozawa
Y
Y
Hatano
M
M
Horie
T
T
Ookawa
N
N
D015308:Anaerobic Threshold; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000097:blood; D006339:Heart Rate; D006801:Humans; D009203:Myocardial Infarction / Q000534:rehabilitation*; D010100:Oxygen / Q000097:blood; D010806:Physical Education and Training
D002245:Carbon Dioxide; D010100:Oxygen