A high carbohydrate diet with a low glycaemic index improves training effects in male endurance athletes

Figures & data

Table 1. Baseline data for the analysed population (n = 28).

	HGI-G (n = 9)	LGI-G (n = 10)	HFLC-G (n = 9)
Age [year]	27.2 ± 9.00	24.2 ± 2.30	24.8 ± 4.21
Height [m]	1.82 ± 0.08	1.77 ± 0.06	1.79 ± 0.06
Body weight [kg]	76.6 ± 11.0	72.6 ± 11.2	78.4 ± 7.55
BMI [kg*m^−2]	22.9 ± 1.56	23.2 ± 2.53	24.5 ± 1.88
Fat free mass [kg]	63.7 ± 7.54	60.5 ± 7.77	63.3 ± 5.53
Fat mass [kg]	12.9 ± 4.36	12.0 ± 4.23	15.0 ± 4.60
Physical activity [h/week]	7.79 ± 2.65	7.88 ± 2.83	7.15 ± 2.60

Data represent mean ± SD. BMI: Body mass index. No significant differences between groups at baseline.

Figure 1. Overview of the study schedule.

Figure 2. Flow chart of subject recruitment, randomisation, and follow up.

Figure 3. Changes in efficacy outcomes. (A) Power at LT; (B) power at IAT; (C) VO_{2 peak}; (D) absolute power output; (E) relative power output. LT: lactate threshold; IAT: individual anaerobic threshold. Data shown as mean ± SD. ^ap < 0.05 between HGI-G and HFLC-G; ^bp < 0.05 between LGI-G and HFLC-G in the post-hoc analysis.

Table 2. Performance-related outcomes of the incremental cycle test at baseline and following the nutritional concepts.

	HGI-G (n = 9)			LGI-G (n = 10)			HFLC-G (n = 9)			p value
	T0	T4	dcohen	T0	T4	dcohen	T0	T4	dcohen	ANOVA
Power at LT [W]	130.1 ± 16.7	133.4 ± 17.4	0.194	128.7 ± 13.2	133.5 ± 20.6	0.277	136.3 ± 17.5	146.1 ± 17.9*	0.554	0.436
Power at IAT [W]	188.7 ± 23.6	193.6 ± 28.1	0.189	183.5 ± 23.0	192.3 ± 30.1	0.329	195.7 ± 29.2	203.3 ± 24.2	0.283	0.757
VO2 peak [mL*kg^−1*min^−1]	49.7 ± 5.15	50.5 ± 6.52	0.136	52.9 ± 4.29	52.9 ± 5.84	0.000	50.4 ± 7.56	48.3 ± 6.55	0.297	0.121
Absolute peak power [W]	266.1 ± 22.4	276.0 ± 29.2*	0.380	269.7 ± 29.5	278.9 ± 38.3	0.269	278.0 ± 37.6	266.4 ± 38.7	0.304	0.009
Relative peak power [W*kg^−1]	3.55 ± 0.290	3.72 ± 0.451	0.448	3.75 ± 0.344	4.00 ± 0.443*	0.630	3.52 ± 0.526	3.48 ± 0.483	0.079	0.036

Data represent mean ± SD. LT: lactate threshold; IAT: individual anaerobic threshold. d_cohen is the effect size for comparison between baseline and final examination. p value ANOVA is the differences between groups with one-way ANOVA. *p < 0.05 within the group from baseline to final examination. Bold numbers represent statistical significance of the efficacy endpoints.

Data availability statement

The datasets generated for this study are available on request to the corresponding author.