Validity and Reliability of the 3-Minute All-Out Test in National and International Competitive Swimmers

Purpose : To assess the concurrent and predictive validity of the 3-minute all-out test (3MT) against conventional methods (CM) of determining critical speed (CS) and curvature constant ( D ′) and to examine the test–retest reliability of the 3MT in highly trained swimmers. Methods : Thirteen highly trained swimmers (age 16 [2] y, weight 64.7 [8.5] kg, height 1.76 [0.07] m) completed 4 time trials and two 3MTs over 2 wk. The distance–time (DT) and speed–1/time (1/ T ) models were used to determine CS and D ′ from 4 time trials. CS 3MT and were determined as the mean speed in the final 30 s of 3MT and as the speed–time integral above CS, respectively. Results : CS 3MT (1.33 [0.06] m·s −1 ) did not differ from CS CM (1.33 [0.06] m·s −1 , P > .05) and correlated nearly perfectly with CS CM ( r = .95, P < .0001). (19.50 [3.52] m) was lower than (23.30 [6.24] m, P < .05) and (22.15 [5.75] m, P = .09). Correlations between and were very large ( r = .79, P = .002). CS and D ′ between the two 3MT trials were not different (CS mean change = −0.009 m·s −1 , P = .102; D ′ mean change = 0.82 m, P = .221). Correlations between the two 3MT trials were nearly perfect and very large for CS ( r = .97) and D ′ ( r = .87, P < .05), respectively, with coefficients of variation of 0.9% for CS and 9.1% for D ′. Conclusion : The 3MT is a valid protocol for estimation of CS and produces high test–retest reliability for CS and D ′ in highly trained swimmers.