Table 2 Cardio-respiratory and biomechanical values for our 8 well-trained male cross-country skiers while roller-skiing with the diagonal stride (DIA) or double poling (DP) technique at 90% VO 2max/peak on a treadmill
First session of DIA | DP | Second session of DIA | F -value | P -value | Power | |
|---|---|---|---|---|---|---|
Cardio-respiratory parameters | ||||||
VO2 (l⋅min−1) | 4.89 ± 0.36# | 4.36 ± 0.49*† | 4.99 ± 0.11# | F (1.2,8.6) = 35.3 | P < 0.001 | 1.000$ |
Heart rate (beats · min−1) | 174 ± 4† | 168 ± 7† | 181 ± 4*# | F (2,14) = 14.7 | P < 0.001 | 0.994 |
V E (l · min−1) | 152 ± 8† | 155 ± 18 | 172 ± 14* | F (2,14) = 8.52 | P = 0.004 | 0.921 |
O2 pulse (ml per beat) | 28.1 ± 2.4# | 25.8 ± 3.1* | 27.3 ± 2.2 | F (1.1,7.8) = 5.77 | P = 0.041 | 0.581$ |
Breaths · min−1 | 47 ± 2#† | 52 ± 3* | 53 ± 7* | F (1.2,8.3) = 6.79 | P = 0.027 | 0.672$ |
V T (ml) | 3.24 ± 0.23# | 2.97 ± 0.39*† | 3.23 ± 0.27# | F (2,14) = 5.43 | P = 0.018 | 0.760 |
Respiratory exchange ratio | 1.07 ± 0.06 | 1.11 ± 0.06 | 1.09 ± 0.04 | F (2,14) = 1.74 | n.s. | |
V E /VO2 | 31.2 ± 1.9#† | 35.6 ± 2.1* | 34.9 ± 3.8* | F (2,14) = 14.7 | P < 0.001 | 0.994 |
V E /VCO2 | 29.1 ± 1.1#† | 31.9 ± 1.4* | 32.0 ± 2.7* | F (2,14) = 10.7 | P = 0.002 | 0.966 |
Biomechanical parameters | ||||||
Speed (km∙h−1) | 11.2 ± 0.3 | 24.3 ± 1.1 | 11.2 ± 0.3 | |||
Cycle rate (Hz) | 0.79 ± 0.02# | 0.87 ± 0.02*† | 0.78 ± 0.01# | F (2,14) = 13.1 | P = 0.001 | 0.985 |
Cycle length (m) | 3.94 ± 0.06# | 7.82 ± 0.23*† | 4.00 ± 0.05# | F (2,14) = 211 | P = 0.001 | 1.000 |
Cycle time (s) | 1.28 ± 0.07# | 1.16 ± 0.00*† | 1.30 ± 0.06# | F (2,14) = 12.3 | P = 0.001 | 0.979 |
Recovery time for the arms (s) | 0.75 ± 0.06# | 0.80 ± 0.06*† | 0.75 ± 0.05# | F (2,14) = 4.91 | P = 0.028 | 0.693 |
Relative arm recovery time (% cycle time) | 58.7 ± 2.5# | 68.9 ± 1.6*† | 57.9 ± 2.7# | F (2,14) = 155 | P = 0.001 | 1.000 |
Peak pole force (N) | 101 ± 7.4# | 287 ± 45.2*† | 96.0 ± 5.5# | F (2,14) = 22.3 | P = 0.001 | 1.000 |
Recovery time for the legs (s) | 0.50 ± 0.04 | 0.52 ± 0.03 | n.s. | |||
Peak leg force (N) | 666 ± 87 | 673 ± 80 | n.s. | |||
Impulse of pole force (Ns) | 33.6 ± 5.9 | 39.4 ± 9.6 | 30.9 ± 3.7 | F (2,14) = 4.49 | P = 0.035 | 0.651 |
Impulse of foot force (Ns) | 481 ± 100 | 392 ± 54† | 482 ± 79# | F (2,14) = 9.47 | P = 0.003 | 0.937 |