Table 2.  Selected physiological responses and maximal running speed reached at the end of the different 30-15IFT protocols. Data are means (±SD).
 

Group A

Group B

 

30-15IFT

30-15IFT-LINE

30-15IFT-CONT

30-15IFT

30-15IFT-28m

VIFT (km·h-1)

19.7 (1.2)

21.7 (1.9) *

16.1 (1.0) *†

18.8 (2.1)

18.7 (1.8)

HRpeak (b·min-1)

197 (10)

197 (7)

194 (8)

198 (9)

199 (9)

HR/speed

3.9 (.8)

3.4 (.6)

5.8 (1.1) *†

4.2 (1.0)

3.9 (.8) §

[La]b (mmol·L-1)

12.3 (2.5)

11.3 (2.6)

9.6 (3.2) *

11.3 (2.1)

11.5 (2.8)

RPE

9 (1)

9 (1)

8 (1)

8 (1)

8 (1)

VIFT : maximal running speed, HRpeak : peak heart rate, [La]b : blood lactate concentration, RPE : rating of perceived exertion, 30-15IFT : original 30-15IFT, 30-15IFT-CONT : modified version of the 30-15IFT without a rest period, 30-15IFT-LINE : modified version of the 30-15IFT without change of direction, 30-15IFT-28m : modified version of the 30-15IFT with 28-m shuttles. *: difference vs. 30-15IFT (p < 0.05) †: difference vs. 30-15IFT-LINE (p < 0.05) ‡: difference vs. 30-15IFT-LINE with effect size considered as moderate (>0.5) §: difference vs. 30-15IFT-LINE with effect size considered as small (0.2<ES≤0.5)