This study compares the physical and training characteristics of top-class marathon runners (TC), i.e., runners having a personal best of less than 2 h 11 min for males and 2 h 32 min for females, respectively, versus high-level (HL) (< 2 h 16 min and < 2 h 38 min). Twenty marathon runners (five TC and HL in each gender) ran 10 km at their best marathon performance velocity (vMarathon) on a level road. This velocity was the target velocity for the Olympic trials they performed 8 wk later. After a rest of 6 min, they ran an all-out 1000-m run to determine the peak oxygen consumption on flat road (.VO(2peak)). Marathon performance time (MPT) was inversely correlated with .VO(2peak). (r = -0.73, P < 0.01) and predicted 59% of the variance of MPT. Moreover, TC male marathon runners were less economical because their energy cost of running (Cr) at marathon velocity was significantly higher than that of their counterparts (212 +/- 17 vs 195 +/- 14 mL.km(-1).kg(-1), P = 0.03). For females, no difference was observed for the energetic characteristics between TC and HL marathon runners. However, the velocity reached during the 1000-m run performed after the 10-km run at vMarathon was highly correlated with MPT (r = -0.85, P < 0.001). Concerning training differences, independent of the gender, TC marathon runners trained for more total kilometers per week and at a higher velocity (velocity over 3000 m and 10,000 m). The high energy output seems to be the discriminating factor for top-class male marathon runners who trained at higher relative intensities.

Interval training at V˙O2max: effects on aerobic performance and overtraining markers. Med. Sci. Sports Exerc., Vol. 31, No. 1, pp. 156-163, 1999. Between inefficient training and overtraining, an appropriate training stimulus (in terms of intensity and duration) has to be determined in accordance with individual capacities. Interval training at the minimal velocity associated with V˙O2max (vV˙O2max) allows an athlete to run for as long as possible at V˙O2max. Nevertheless, we don't know the influence of a defined increase in training volume at vV˙O2max on aerobic performance, noradrenaline, and heart rate. Eight subjects performed 4 wk of normal training (NT) with one session per week at vV˙O2max, i.e., five repetitions run at 50% of the time limit at vV˙O2max, with recovery of the same duration at 60% vV˙O2max. They then performed 4 wk of overload training (OT) with three interval training sessions at vV˙O2max. Normal training significantly improved their velocity associated with V˙O2max (20.5 ± 0.7 vs 21.1 ± 0.8 km·h−1, P = 0.02). As a result of improved running economy (50.6 ± 3.5 vs 47.5 ± 2.4 mL·min−1·kg−1, P = 0.02), V˙O2max was not significantly different (71.6 ± 4.8 vs 72.7 ± 4.8 mL·min−1·kg−1). Time to exhaustion at vV˙O2max was not significantly different (301 ± 56 vs 283 ± 41 s) as was performance (i.e., distance limit run at vV˙O2max: 2052.2 ± 331 vs 1986.2 ± 252.9 m). Heart rate at 14 km·h−1 decreased significantly after NT (162 ± 16 vs 155 ± 18 bpm, P < 0.01). Lactate threshold remained the same after normal training (84.1 ± 4.8% vV˙O2max). Overload training changed neither the performance nor the factors concerning performance. However, the submaximal heart rate measured at 14 km·h−1 decreased after overload training (155 ± 18 vs 150 ± 15 bpm). The maximal heart rate was not significantly different after NT and OT (199 ± 9.5, 198 ± 11, 194 ± 10.4, P = 0.1). Resting plasma norepinephrine (veinous blood sample measured by high pressure liquid chromatography), was unchanged (2.6 vs 2.4 nm·L−1, P = 0.8). However, plasma norepinephrine measured at the end of the vV˙O2max test increased significantly (11.1 vs 26.0 nm·L−1, P = 0.002). Performance and aerobic factors associated with the performance were not altered by the 4 wk of intensive training at vV˙O2max despite the increase of plasma noradrenaline.