Table 3

Overview of fitness reliability studies carried out within the framework of the ALPHA study

AuthorParticipantsAge (years)TestDesign/time intervalMain outcomeConclusion
España-Romero et al13Boys = 17, girls = 56–12Handgrip strengthTest–retest (2 h)Reliability coefficients=0.97 and 0.98 for right and left hands, respectively. The one-way ANOVA for repeated measures did not show a statistical difference between the test and retest results (p=0.99 and 0.40 for the right and left hands, respectively). A significant correlation between the test and retest results was obtained for right (r=0.92, p<0.001) and left (r=0.97, p<0.001) handsHigh reliability coefficients, significant correlation and no statistical difference were found between the test and retest results
Ortega et al20Boys = 69, girls = 5413.6 ± 0.820mSRT, standing broad jump, handgrip strength, bent arm hang, 4×10mSRT, back saver sit and reachTest–retest (2 weeks)Mean inter-trials difference (bias) ± SD:20mSRT (stages)= −0.1 ± 1.5 for boys, 0.0 ± 1.1 for girls; standing broad jump (cm)= −0.3 ± 12.9 for boys, 0.3 ± 9.0 for girls; handgrip strength (kg)= 0.3 ± 2.5 for boys, 0.0 ± 1.8 for girls; bent arm hang (s)= −0.7 ± 13.9 for boys, 0.0 ± 16.3 for girls; 4×10mSRT (s)= 0.1 ± 0.7 for boys, 0.1 ± 0.8 for girls; back saver sit and reach (cm)= −0.3 ± 3.6 for boys, 1.4 ± 4.9 for girlsNeither systematic bias nor sex differences were found for any of the studied tests, suggesting an acceptable reliability
España-Romero et al15Boys = 31, girls = 3512–16Handgrip strengthTest–retest with known weights (40–60 s)The observed mean inter-trials difference (bias) was 0.23, 0.26 and 0.02 for the Jamar, DynEx and TKK dynamometers, respectively (all p>0.05), whereas 95% limits of agreements were 1.20, 1.42 and 1.57, respectively. No patterns of heteroscedasticity were observed with any of the dynamometersAmong the three dynamometers studied, the TKK dynamometer seems to be the most reliable for measuring maximal handgrip strength in this particular population
España-Romero et al2158 Children, 80 adolescents6–1820mSRT, standing broad jump, handgrip strength, weight, height, triceps and subscapular skinfolds, waist circumferenceTest–retest (1 week)Significant inter-trials differences were found only for height in children (inter trial difference: 0.73 ± 0.8 cm, p<0.05), waist circumference for both children (−0.82 ± 1.2, p<0.05) and adolescents (−0.35 ± 0.8, p<0.05), and in standing broad jump test only for children (3.8 ± 12.7 cm, p<0.05)A health-related fitness test battery including the 20mSRT, handgrip and standing broad jump tests and measures on weight, height, triceps and subscapular skinfolds, and waist circumference administered by PE teachers in the school setting can be considered reliable, feasible and safe
  • ANOVA, analysis of variance; PE, physical education; SRT, shuttle run test.