Enhanced Endurance Performance by Periodization of Carbohydrate Intake: “Sleep Low” Strategy

    loading  Checking for direct PDF access through Ovid

Abstract

Purpose

We investigated the effect of a chronic dietary periodization strategy on endurance performance in trained athletes.

Methods

Twenty-one triathletes (V˙O2max: 58.7 ± 5.7 mL·min−1·kg−1) were divided into two groups: a “sleep-low” (SL) (n = 11) and a control (CON) group (n = 10) consumed the same daily carbohydrate (CHO) intake (6 g·kg−1·d−1) but with different timing over the day to manipulate CHO availability before and after training sessions. The SL strategy consisted of a 3-wk training–diet intervention comprising three blocks of diet–exercise manipulations: 1) “train-high” interval training sessions in the evening with high-CHO availability, 2) overnight CHO restriction (“sleeping-low”), and 3) “train-low” sessions with low endogenous and exogenous CHO availability. The CON group followed the same training program but with high CHO availability throughout training sessions (no CHO restriction overnight, training sessions with exogenous CHO provision).

Results

There was a significant improvement in delta efficiency during submaximal cycling for SL versus CON (CON, +1.4% ± 9.3%; SL, +11% ± 15%, P < 0.05). SL also improved supramaximal cycling to exhaustion at 150% of peak aerobic power (CON, +1.63% ± 12.4%; SL, +12.5% ± 19.0%; P = 0.06) and 10-km running performance (CON, −0.10% ± 2.03%; SL, −2.9% ± 2.15%; P < 0.05). Fat mass was decreased in SL (CON, −2.6 ± 7.4; SL, −8.5% ± 7.4% before; P < 0.01), but not lean mass (CON, −0.22 ± 1.0; SL, −0.16% ± 1.7% PRE).

Conclusion

Short-term periodization of dietary CHO availability around selected training sessions promoted significant improvements in submaximal cycling economy, as well as supramaximal cycling capacity and 10-km running time in trained endurance athletes.

Related Topics

    loading  Loading Related Articles