The physiological effects of breath‐holding during high‐intensity exercise

Figures

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  FIGURE 1. Heart rate and muscle oxygenation during exercise. Data presented are mean (symbols) ± standard deviation (error bars) for the baseline period and in 5 s bins for the 20 s exercise period for (a) heart rate, and changes from baseline in (b) muscle oxygen saturation (ΔSmO2), (c) total hemoglobin (Δ[THb]), and (d) deoxygenated hemoglobin (Δ[HHb]). Gray lines represent individual responses. n = 20 for all panels. μM, micromoles; BH, breath‐holding (black circles); bpm, beats per minute; FB, free‐breathing (white circles).

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  FIGURE 2. Blood pressure, lactate, and gas exchange and ventilatory data. Data presented are mean (bars) ± standard deviation (error bars) of pre‐ and post‐exercise measures for (a) systolic and (b) diastolic blood pressures (BP), and (c) blood lactate; the 5 s immediately pre‐ and post‐exercise for (d) rate of oxygen uptake (V̇O2), (e) rate of carbon dioxide production (V̇CO2), and (f) minute ventilation (V̇E); and the final breath pre‐ and first breath post‐exercise for end‐tidal partial pressures of (g) oxygen (PetO2) and (h) carbon‐dioxide (PetCO2). Lines represent individual responses. n = 20 for all panels. BH, breath‐holding (gray bars); FB, free‐breathing (white bars); L.min−‐1, liters per minute; mmHg, millimeters of mercury; mmol.L−1, millimols per liter; Post, post‐exercise; Pre, pre‐exercise.

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  FIGURE 3. Heart rate and muscle oxygenation during recovery. Data presented are mean (symbols) ± standard deviation (error bars) of the 1 min bins of the first 5 min post exercise for (a) heart rate, and changes from baseline in (b) muscle oxygen saturation (ΔSmO2), (c) total hemoglobin (Δ[THb]), and (d) deoxygenated hemoglobin (Δ[HHb]). Gray lines represent individual responses. n = 20 for all panels. μM = micromoles; BH, breath‐holding (black circles); bpm, beats per minute; FB, free‐breathing (white circles).

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  FIGURE 4. Gas exchange and ventilatory data during recovery. Data presented are mean (symbols) ± standard deviation (error bars) of the 1 min bins of the first 5 min post exercise for (a) rate of oxygen uptake (V̇O2), (b) rate of carbon dioxide production (V̇CO2), and (c) minute ventilation (V̇E). Gray lines represent individual responses. n = 20 for all panels. BH, breath‐holding (black circles); FB, free‐breathing (white circles); L.min−1, liters per minute.