Dataset Information

Cycling Efficiency During Incremental Cycle Ergometry After 24 Hours of Overfeeding or Fasting.

ABSTRACT: OBJECTIVE:The objective of this study was to determine whether net cycling efficiency (NET) is altered by 24-hour fasting or overfeeding and whether it correlates with dietary-related energy expenditure (EE) and future weight change. METHODS:In a crossover design, healthy subjects fasted or were overfed for 24 hours while in a whole-room calorimeter using five diets with doubled energy needs: standard, high-carbohydrate (75%), high-fat (60%), high-protein (30%), and low-protein (3%) diets. Graded cycling exercise at low power outputs (10-25-50 W) was performed the day before and after each dietary intervention. RESULTS:NET did not change following any dietary intervention (all P?>?0.05 vs. 0). Individual changes in NET did not correlate with EE responses to dietary interventions. However, the change in NET after low-protein overfeeding was inversely correlated with baseline body fat (r?=?-0.60, P?=?0.01); that is, NET increased in lean but decreased in overweight subjects (??=?0.010?±?0.010 vs. -0.013?±?0.009, P?=?0.0003). Increased NET following the low-protein diet was associated with weight gain after 6 months (r?=?0.60, P?=?0.05). CONCLUSIONS:Despite no substantial effect of acute overfeeding or fasting on NET, the change in NET following low-protein overfeeding depends on adiposity and may influence weight change, suggesting that increased efficiency in a setting of protein scarcity is an adaptive response that may ultimately lead to weight gain.

SUBMITTER: Vinales KL

PROVIDER: S-EPMC5783742 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Cycling Efficiency During Incremental Cycle Ergometry After 24 Hours of Overfeeding or Fasting.

Vinales Karyne L KL Schlögl Mathias M Reinhardt Martin M Thearle Marie S MS Krakoff Jonathan J Piaggi Paolo P

Obesity (Silver Spring, Md.) 20171225 2

<h4>Objective</h4>The objective of this study was to determine whether net cycling efficiency (NET) is altered by 24-hour fasting or overfeeding and whether it correlates with dietary-related energy expenditure (EE) and future weight change.<h4>Methods</h4>In a crossover design, healthy subjects fasted or were overfed for 24 hours while in a whole-room calorimeter using five diets with doubled energy needs: standard, high-carbohydrate (75%), high-fat (60%), high-protein (30%), and low-protein (3 ...[more]

PMID: 29276860

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Dataset Information

Cycling Efficiency During Incremental Cycle Ergometry After 24 Hours of Overfeeding or Fasting.

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Cycling Efficiency During Incremental Cycle Ergometry After 24 Hours of Overfeeding or Fasting.

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