Reduced cardiovascular and metabolic responses during eccentric stepping exercise: A pilot study.
Physiol Rep
; 12(19): e70080, 2024 Oct.
Article
in En
| MEDLINE
| ID: mdl-39370300
ABSTRACT
This study compared cardiovascular and metabolic responses during concentric and eccentric stepping. Eight participants (5 m, 3f; 22 ± 2 years) performed maximal concentric and eccentric ramp incremental tests on a modified stepping ergometer. Subsequently, three randomized 15-min constant-power tests were performed (1) concentric stepping at 90% of the concentric lactate threshold (LT), (2) eccentric stepping at the same power, and (3) eccentric stepping at the same oxygen uptake (VÌO2). At equivalent power (36 ± 6 W, p = 0.62), eccentric stepping resulted in 46 ± 8% lower VÌO2, 16 ± 6% lower heart rate (HR), and 11 ± 5% lower mean arterial blood pressure compared to concentric (p < 0.01). Matching VÌO2 required 65 ± 19% more power during eccentric stepping (p < 0.01). During this test, eccentric VÌO2 and HR continued to increase, resulting in a 22 ± 29% higher VÌO2 and 19 ± 16% higher HR in the final minute (p < 0.001). Reduced cardiorespiratory demand during eccentric stepping at the same power as concentric demonstrates a higher eccentric power is required to produce the same VÌO2. However, despite being below the concentric LT, eccentric VÌO2 and HR continued to increase past the predicted steady state, indicating a higher exercise intensity.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Oxygen Consumption
/
Exercise
/
Heart Rate
Limits:
Adult
/
Female
/
Humans
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Male
Language:
En
Journal:
Physiol Rep
/
Physiol. reports
/
Physiological reports
Year:
2024
Document type:
Article
Country of publication: