Deportistas de alta competición con índice de masa corporal igual o mayor a 30 kg/m2. ¿Obesidad o gran desarrollo muscular?

Abstract

The aim of this paper is to examine athletes whose BMI is in the obesity range, and to determine the relationship between their adiposity indices and their body fat measured by anthropometry, while establishing which would be the most valid for this population.

A retrospective study was carried out on athletes with a BMI of 30 kg/m² or higher. The sample consisted of 173 athletes (151 males and 22 females), aged 23.3 ± 4.9, with 9.8 ± 5 years in competition, training 16.6 ± 7.1 hours/week. The protocol included 15 variables and the calculation of anthropometric indices related to adiposity and body fat. ROC curves were used to check the level of diagnostic accuracy in relation to obesity (high fat percentage).

The anthropometric variables with the greatest area under the curve were skinfolds and, in particular, supraspinale skinfolds (95% CI: 0.899-0.974), with a cut-off point of 21 mm. These were followed by waist circumference to height ratio (95% CI: 0.784-0.916) with a cut-off point of 0.57. As many as 72% of the athletes would have been wrongly classified as obese by their BMI. It was established that a BMI of up to 32.8 kg/m² may be considered as overweight for males, mainly due to their lean or fat-free mass.

In order to diagnose obesity in athletes, body fat should be assessed by means of skinfold measurements or, failing that, by measuring waist circumference to height ratios.