Acute Physiological and Perceptual Responses to Six Body-Weight Squat Exercise Variations

Adequate exercise prescription requires a deep understanding of the body's response to exercise. This study explored the responses of heart rate (HR), muscle oxygen saturation (SmO₂), and perceived exertion (RPE) during six body-weight squat exercise variations. A total of 15 recreationally active participants (age: 28.2 ± 8.0 years; body mass: 71.1 ± 11.2 kg; height: 1.73 ± 0.08 m) were recruited. Six body-weight squat variations (deep, jumping, single-leg, uneven, unstable, and wall-sit) were randomly performed for 90 s. Results revealed that the jumping squat promoted a higher average and peak HR (165.3 ± 14.5 and 146.1 ± 14.8 bpm, respectively), and a lower average SmO₂ and higher deoxygenation SmO₂ in the soleus muscle (40.3 ± 15.4 and 46.0 ± 11.4%, accordingly). No differences were observed in recovery time or in the same SmO₂ derived-parameters in the vastus lateralis muscle. The jumping variation promoted a greater response at a physiological level, both centrally, related to cardiovascular response, and peripherally, related to soleus SmO₂. It was also the more demanding variation at both the overall and lower limb muscular level of RPE. This holistic view allows a precise identification of the response patterns in body-weight squat exercise variations to an acute session, with a training intervention providing additional information.