Introduction For an assessment to have value, it must measure the parameter of interest and be reliable enough to detect small differences. To minimise TEM differences between repeat skinfold measures, measurement sites and measurement techniques have been defined by the International Society for the Advancement of Kinanthropometry (ISAK). The aim of this study, therefore, was to examine the significance of accurate skinfold measurement site location in order to confirm or relax the specific protocols that ISAK has defined.

Methods Nine measurements, in a 1-cm grid pattern, centred on each of the eight ISAK-specified skinfold sites, were taken three times at each grid point by each of the two ISAK criteria (level 4) measurers using Harpenden skinfold callipers, on 12 healthy participants (11 males and 1 female; 27.1 ± 6.5 years; 177.3 ± 7.4 cm; 77.8 ± 12.7 kg).

Results Skinfolds taken at the eight peripheral grid points were generally different (45 out of 64 = 70%) from the skinfolds taken at the central ISAK grid point. The effect was multidirectional. The subscapular was the most robust site in terms of least effect with deviation away from the central point. All other skinfold sites showed some variation with most care needed in marking the biceps and triceps sites.

Discussion/conclusion Measuring 1 cm away from a defined ISAK site produced significant differences in the majority of skinfold measurement values obtained. No site was totally free from this variation. Therefore, adherence to identifying, marking and measuring at the defined site is essential.