TY - JOUR
T1 - Factors underlying the perception of effort during constant heart rate running above and below the critical heart rate
AU - Bergstrom, Haley C.
AU - Housh, Terry J.
AU - Cochrane, Kristen C.
AU - Jenkins, Nathaniel D.M.
AU - Zuniga, Jorge M.
AU - Buckner, Samuel L.
AU - Goldsmith, Jacob A.
AU - Schmidt, Richard J.
AU - Johnson, Glen O.
AU - Cramer, Joel T.
PY - 2015/10/22
Y1 - 2015/10/22
N2 - Purpose: This study examined: (1) the sustainability of the critical heart rate (CHR) minus 5 b min−1 (CHR − 5) and CHR plus 5 b min−1 (CHR + 5); (2) the ratings of perceived exertion (RPE), velocity, $$ \dot{V}O_{2} $$V˙O2, minute ventilation ($$ \dot{V}_{E} $$V˙E), breathing frequency (fb), and electromyographic amplitude (EMG AMP) and EMG mean power frequency (MPF) responses during treadmill running at CHR − 5 and CHR + 5 to determine what factors underlie the perception of effort when heart rate (HR) is held constant; and (3) the relationships among RPE, $$ \dot{V}O_{2} $$V˙O2, and HR, to determine which variable(s) reflect exhaustion during exercise performed at a constant HR. Methods: The CHR was determined in eight runners (mean ± SD; age = 24 ± 3 years) from a series of four exhaustive, constant velocity runs. The RPE, velocity, $$ \dot{V}O_{2} $$V˙O2, $$ \dot{V}_{E} $$V˙E, fb, EMG AMP, and EMG MPF responses were recorded during runs at the CHR − 5 and CHR + 5. Results: At CHR − 5, RPE, fb, and EMG MPF increased, while velocity, $$ \dot{V}O_{2} $$V˙O2, $$ \dot{V}_{E} $$V˙E, and EMG AMP decreased. At CHR + 5, RPE and fb increased, velocity, $$ \dot{V}O_{2} $$V˙O2, $$ \dot{V}_{E} $$V˙E, and EMG AMP decreased, and EMG MPF remained constant. Conclusions: The close association between fb and RPE throughout the run at CHR − 5 and during the last 50 % of the run at CHR + 5 indicated that muscle afferents may have provided feedback from metabolic and mechanical stimuli that contributed to the perceptual responses. In addition, only RPE consistently indicated exhaustion and the current findings supported its use to monitor exercise performed at a constant HR.
AB - Purpose: This study examined: (1) the sustainability of the critical heart rate (CHR) minus 5 b min−1 (CHR − 5) and CHR plus 5 b min−1 (CHR + 5); (2) the ratings of perceived exertion (RPE), velocity, $$ \dot{V}O_{2} $$V˙O2, minute ventilation ($$ \dot{V}_{E} $$V˙E), breathing frequency (fb), and electromyographic amplitude (EMG AMP) and EMG mean power frequency (MPF) responses during treadmill running at CHR − 5 and CHR + 5 to determine what factors underlie the perception of effort when heart rate (HR) is held constant; and (3) the relationships among RPE, $$ \dot{V}O_{2} $$V˙O2, and HR, to determine which variable(s) reflect exhaustion during exercise performed at a constant HR. Methods: The CHR was determined in eight runners (mean ± SD; age = 24 ± 3 years) from a series of four exhaustive, constant velocity runs. The RPE, velocity, $$ \dot{V}O_{2} $$V˙O2, $$ \dot{V}_{E} $$V˙E, fb, EMG AMP, and EMG MPF responses were recorded during runs at the CHR − 5 and CHR + 5. Results: At CHR − 5, RPE, fb, and EMG MPF increased, while velocity, $$ \dot{V}O_{2} $$V˙O2, $$ \dot{V}_{E} $$V˙E, and EMG AMP decreased. At CHR + 5, RPE and fb increased, velocity, $$ \dot{V}O_{2} $$V˙O2, $$ \dot{V}_{E} $$V˙E, and EMG AMP decreased, and EMG MPF remained constant. Conclusions: The close association between fb and RPE throughout the run at CHR − 5 and during the last 50 % of the run at CHR + 5 indicated that muscle afferents may have provided feedback from metabolic and mechanical stimuli that contributed to the perceptual responses. In addition, only RPE consistently indicated exhaustion and the current findings supported its use to monitor exercise performed at a constant HR.
KW - Constant heart rate exercise
KW - Critical heart rate
KW - Critical power
KW - Critical velocity
KW - Ratings of perceived exertion
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U2 - 10.1007/s00421-015-3204-y
DO - 10.1007/s00421-015-3204-y
M3 - Article
C2 - 26108674
AN - SCOPUS:84941879651
VL - 115
SP - 2231
EP - 2241
JO - European Journal of Applied Physiology
JF - European Journal of Applied Physiology
SN - 1439-6319
IS - 10
ER -