Research

Mixed

Training with reduced carbohydrate availability does not necessarily improve exercise performance (e.g., time trial performance) despite enhancing molecular markers of adaptation.

Do not expect that training with low carbs will automatically make you faster. While it improves your body's metabolic efficiency, it may blunt your ability to train at high intensities. Use 'train low' strategically for specific sessions, but ensure you also train 'high' (with adequate carbs) to maintain your speed and power capacity for races.

GoodRefutesHIGH confidence
although train-low augmented these markers of training adaptation, exercise performance (1-h time trial) was not improved accordingly.
Jonathan D. Bartlett et al. · European Journal of Sport Science · 2014

Why this rating

Consistently reported across multiple cited studies (Yeo, Hulston).

Source

Carbohydrate availability and exercise training adaptation: Too much of a good thing?

Jonathan D. Bartlett et al. · European Journal of Sport Science · 2014

DOI 10.1080/17461391.2014.920926

narrative_reviewCited 225×
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DOI resolved against Crossref · corpus check 2026-06-10

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