Metabolic and Perceptual Responses to Constant Heart Rate Exercise at Vigorous Intensities in Women.
Med Sci Sports Exerc
; 56(5): 917-926, 2024 May 01.
Article
in En
| MEDLINE
| ID: mdl-38233976
ABSTRACT
PURPOSE:
This study quantified the metabolic demands (oxygen uptake (VÌO 2 )), power output adjustments, changes in the VÌO 2 /power output ratio, and perceptual responses (rating of perceived exertion (RPE)) during constant heart rate (HR) exercise performed within the vigorous intensity range (77%-95% HR peak ).METHODS:
Twelve women (mean ± SD age, 22 ± 4 yr) performed a graded exercise test to exhaustion to determine peak parameters, and three randomly ordered, constant HR trials to exhaustion or for 60 min at the lower (HR L = 77% HR peak ), middle (HR M = 86% HR peak ), and higher (HR H = 95% HR peak ) end of the vigorous intensity range. Time course of changes and patterns of responses were examined for VÌO 2 , power output, VÌO 2 /power output, and RPE for the composite and for each subject.RESULTS:
Across the HR L (time to exhaustion ( Tlim ) = 56.3 ± 9.9 min), HR M (51.8 ± 13.5 min), and HR H (27.2 ± 17.7 min) trials, VÌO 2 and power output decreased quadratically ( P < 0.05) relative to the initial value from 10% to 100% of Tlim , whereas the VÌO 2 /power output increased quadratically from 20% to 100% Tlim , and RPE increased linearly from 50% to 100% Tlim . The VÌO 2 and RPE, collapsed across time, for HR L (54.3% ± 3.3% VÌO 2peak , 11 ± 1.5 RPE) were lower than HR M (64.9% ± 4.5% VÌO 2peak , 14 ± 1.7 RPE), and both were lower than HR H (80.1% ± 4.1% VÌO 2peak , 17 ± 1.4 RPE). None of the 12 subjects at HR L , 6 at HR M , and 7 at HR H were within the vigorous VÌO 2 range.CONCLUSIONS:
The HR L was not sufficient to meet the desired metabolic intensity for vigorous exercise, whereas the middle to higher end of the range elicited a VÌO 2 within the prescribed range of only ~50%-60% of the subjects. This study indicated that exercise held constant at a percentage of HR peak cannot consistently be used to prescribe a desired metabolic stimulus.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Oxygen Consumption
/
Exercise
Limits:
Adolescent
/
Adult
/
Female
/
Humans
Language:
En
Journal:
Med Sci Sports Exerc
Year:
2024
Document type:
Article