Square-Wave Endurance Exercise Test (SWEET) for training and assessment in trained and untrained subjects

Summary

In order to obtain information about physiological and homeostasic responses at the Maximal Intensity of Endurance of the 45 min “Square-Wave Endurance Exercise Test” (MIE₄₅), three arterial blood samples were taken: (a) at rest; (b) at the 45th min of the SWEET; (c) after 15 min of recovery, to measure p_aO₂, p_aCO₂, [H⁺], [Hb], and [lactate] in 14 normal male subjects: four trained (T) six well trained (WT) and four others untrained (U). Total mechanical work (TMW) corresponding to MIE₄₅ was significantly higher (x ± SEM) respectively in WT (9.22±0.65 kJ·kg⁻¹, p<0.001), than in T (7.17±0.18 kJ·kg⁻¹, p<0.01) and U subjects (4.44±0.36, p<0.001). Because of this the lactate level, which rose significantly during exercise, differed between U and WT subjects (p<0.05). In spite of the exhaustive character of the MIE₄₅, [H⁺] and p_aO₂ remained within the range of normal values. These results suggest that trained and untrained subjects can be trained with the exhausting MIE₄₅ exercise while maintaining a constant [H⁺] and p_aO₂ at the 45th min of exercise.