Acute Responses to Walking, Stair Climbing, and Functional Circuit Exercise

Acute Metabolic, Respiratory, and Neuromotor Responses to Walking, Stair Climbing, and Functional Circuit Exercise in Sedentary Individuals: A Heart Rate-Controlled Randomized Crossover Study

This study evaluated the acute physiological responses to three different exercise modalities in sedentary young men. Participants completed walking, stair climbing, and functional circuit exercise sessions in a randomized crossover design. Each exercise session lasted 20 minutes and was performed at a target intensity of 50% heart rate reserve (±5 beats/min), with at least 72 hours between sessions.

The study compared acute respiratory, metabolic, and neuromotor responses to the three exercise modalities. Pulmonary function was assessed using spirometry, blood lactate concentration was measured using capillary blood samples, and countermovement jump performance was assessed as an indicator of neuromuscular performance. Heart rate was continuously monitored during each exercise session.

Inclusion Criteria:

• Male sex.
• Aged 18-30 years.
• Classified as sedentary/insufficiently active according to the study eligibility criteria.
• Able to safely complete the exercise protocols and study assessments.
• Provided voluntary informed consent.

Exclusion Criteria:

• Current cigarette or electronic cigarette use.
• Known cardiovascular, respiratory, or metabolic disease.
• Regular medication use that could affect physiological responses to exercise.
• Acute infection within the previous 2 weeks.
• Musculoskeletal conditions that could interfere with safe participation in the exercise protocols.
• Any condition requiring medical evaluation before exercise participation.
• Inability to obtain acceptable baseline spirometry measurements according to the study procedures.