Effect of a Mediterranean-style diet on the exercise performance and lactate elimination on adolescent athletes

Abstract

Background/objectives: Mediterranean diet is an environmentally friendly and healthy diet model. The diet offers many vegetables, fruits, nuts, and olive oil to consumers. In addition, it provides moderate amounts of fish and chicken, smaller quantities of dairy products, red meat, and processed meat. The Mediterranean diet has a high anti-inflammatory and antioxidant content, and it causes many physiological changes that can provide a physical performance advantage. This study examined the effects of a 15-day menu, which was planned using foods with a low acid load within the Mediterranean diet rules, on the exercise performance, lactate elimination, anthropometric measurements, and body composition.

Subjects/methods: Fifteen professional male athletes between the ages of 13 and 18, who were engaged in ski running, were included in the experimental study. Dietary intervention was applied for 15 days. The athlete performances were evaluated by applying the vertical jump test, hand grip strength, 20 meters shuttle run test, and Borg fatigue scale. After the shuttle run test (every 3 min for 30 min), blood was drawn from the finger, and the lactate elimination time was calculated. Performance and lactate measurements, body analysis, and anthropometric measurements were taken before and after dietary intervention.

Results: The vertical jump height and hand grip strength increased after the intervention (P < 0.05). The test duration, total distance, the number of shuttles, and maximum oxygen consumption parameters of the shuttle run test increased (P < 0.05). After the intervention, the athletes' perceived fatigue scores decreased in several stages of the shuttle run test (P < 0.05). The lactate elimination time and athlete's body composition were similar in repeated measurements (P > 0.05). In the last measurements, the upper middle arm circumference decreased while the height of the athletes increased (P < 0.05).

Conclusions: These results show that the Mediterranean diet is a safe and feasible dietary approach for aerobic performance and strength increase.

Keywords: Lactates; Mediterranean diet; athletic performance.

Fig. 1. Perceived fatigue scores during speed increment in the shuttle run test (n = 15). Mean values, n = 15 at the 1st, 2nd, 3rd, 4th, 5th, 6th, and 7th stages; n = 14 at the 8th and 9th stages; n = 13 at the 10th stage. Before the diet, n = 6 at the 11th stage, n = 3 at the 12th stage, and n = 1 at the 13th stage. After the diet, n = 9 at the 11th stage, n = 6 at the 12th stage, n = 4 at the 13th stage, and n = 1 at the 14th stage.

^*P < 0.05: Wilcoxon analysis; ^#P < 0.05: dependent sample t-test.

Fig. 2. Mean lactate levels of participants before and after the shuttle run test (n = 15). Mean values. The Wilcoxon test was used to compare lactate levels at 18 and 30 min after exercise. A dependent sample t-test was used for others. P > 0.05 in all comparisons.

Fig. 3. Lactate half-life at rest (sec) (n = 15). Mean values, dependent sample t-test.