Aim: Aim of our study was to evaluate the effects of
interval exercise training (IT) programs, regarding whole body oxygen uptake
and peripheral tissue oxygenation, in Chronic Heart Failure (CHF) patients
during recovery. Methods: Twenty-six CHF patients (21 males/5 females), mean
age of 49 ± 12 years, participated in the study. Fifteen patients were
assigned to IT and 11 patients were assigned to IT followed by strength
training. All patients were trained for 40 minutes per session, 3 times per
week, for 12 weeks. They performed a symptom-limited cardiopulmonary exercise
testing (CPET), before and after the completion of the program. Muscle tissue
oxygen saturation (StO2) of quadriceps femoris was continuously measured by Near Infrared Spectroscopy (NIRS) during CPET and during the recovery
period after the end of exercise. Results: No differences were noted between
the two patient groups regarding whole body and peripheral tissue oxygenation
indices and, therefore, data from all patients were pooled. After training, an
increase in peak oxygen uptake (17 ± 4.5 to 19 ± 5.5 ml/kg/min, p < 0.05),
gas exchange threshold (11 ± 3.5 to 12.5 ± 3.5 ml/kg/min, p < 0.05), peak
work rate achieved (105 ± 29 to 124 ± 37 Watt, p < 0.05) and the first
degree slope of VO2 at the first minute of recovery (0.45 ± 0.2 to
0.61 ±0.3 L/min2, p < 0.05) was noted. In addition, tissue re-oxygenation time
constant was decreased (65 ± 25 to 52 ± 28
sec, p < 0.001). Conclusion: In conclusion, interval exercise training
accelerates oxygen uptake and peripheral tissue oxygenation during recovery from exercise in CHF patients.