Fore more than a decade, the live high-train low (LHTL) approach, developed by Levine and Stray-Gundersen, has been widely used by elite endurance athletes. Originally, it was pointed out, that by living at moderate altitude, athletes should benefit from an increased red cell volume (RCV) and hemoglobin mass (Hb(mass)), while the training at low altitudes should prevent the disadvantage of reduced training intensity at moderate altitude. VO2max is reduced linearly by about 6-8 % per 1000 m increasing altitude in elite athletes from sea level to 3000 m, with corresponding higher relative training intensities for the same absolute work load. With 2 weeks of acclimatization, this initial deficit can be reduced by about one half. It has been debated during the last years whether sea-level training or exposure to moderate altitude increases RCV and Hb(mass) in elite endurance athletes. Studies which directly measured Hb(mass) with the optimized CO-rebreathing technique demonstrated that Hb(mass) in endurance athletes is not influenced by sea-level training. We documented that Hb(mass) is not increased after 3 years of training in national team cross-country skiers. When athletes are exposed to moderate altitude, new studies support the argument that it is possible to increase Hb(mass) temporarily by 5-6 %, provided that athletes spend >400 h at altitudes above 2300-2500 m. However, this effect size is smaller than the reported 10-14 % higher Hb(mass) values of endurance athletes living permanently at 2600 m. It remains to be investigated whether endurance athletes reach these values with a series of LHTL camps.

In orienteering, athletes must choose the quickest route from point to point, considering if they want to run a longer flat distance rather than a shorter distance with an incline to reach the next point. Our aim was therefore, to determine an athlete's equivalence factor (EF, ratio between horizontal and uphill running performance) enabling coaches to provide individual route choice recommendations during orienteering competition. Ten male and 8 female orienteers performed 1 horizontal (MST(horizontal); 0% incline) and 1 uphill (MST(uphill); 22% incline) maximal running stage test to exhaustion on a treadmill in randomized order. The EFs were calculated based on maximal speeds achieved in both tests (MRV(horizontal/uphill)). In addition, VO2peak was measured. MRV(horizontal) was 20.4 ± 0.6 and 17.3 ± 0.8 km · h, and MRV(uphill) was 8.8 ± 0.7 and 7.2 ± 0.5 km · h (men and women). The EF was 6.3 ± 0.7 and ranged between 5.2 and 7.4. Relative VO2peak(uphill) was 69.2 ± 5.7 and 59.1 ± 3.7 m l · kg · min, whereas VO2peak(horizontal) was lower 66.4 ± 3.5 (p < 0.05) and 55.7 ± 3.1 ml · kg · min (p < 0.01) than in VO2peak(uphill). Relative VO2peak(uphill) correlated strongly with MRV(uphill) (men: r = 0.85, p < 0.01; women: r = 0.84, p < 0.01), whereas relative VO2peak(horizontal) showed no strong correlation with MRV(horizontal) (men: r = 0.51, p = 0.12; women: r = 0.41, p = 0.32). These data show that there are relevant differences in the relation between uphill and horizontal running capacity in these athletes. Tailoring the route selection to the athletes' advantage based on the relation between their uphill and horizontal running performance and individual EF may positively impact on overall performance in orienteering competition.

The effect of live high-train low on hemoglobin mass (Hb(mass)) and red cell volume (RCV) in elite endurance athletes is still controversial. We expected that Hbmass and RCV would increase, when using a presumably adequate hypoxic dose. An altitude group (AG) of 10 Swiss national team orienteers (5 men and 5 women) lived at 2,500 m ( 18 h per day) and trained at 1,800 and 1,000 m above sea level for 24 days. Before and after altitude, Hb(mass), RCV (carbon monoxide rebreathing method), blood, iron, and performance parameters were determined. Seven Swiss national team cross-country skiers (3 men and 4 women) served as "sea level" (500 - 1,600 m) control group (CG) for the changes in Hbmass and RCV. The AG increased Hbmass (805 +/- 209 vs. 848 +/- 225 g; P < 0.01) and RCV (2,353 +/- 611 vs. 2,470 +/- 653 ml; P < 0.01), whereas there was no change for the CG (Hb(mass): 849 +/- 197 vs. 858 +/- 205 g; RCV: 2,373 +/- 536 vs. 2,387 +/- 551 ml). Serum erythropoietin (P < 0.001), reticulocytes (P < 0.001), transferrin (P < 0.001), soluble transferrin receptor (P < 0.05), and hematocrit (P < 0.01) increased, whereas ferritin (P < 0.05) decreased in the AG. These changes were associated with an increased maximal oxygen uptake (3,515 +/- 837 vs. 3,660 +/- 770 ml/min; P < 0.05) and improved 5,000-m running times (1,098 +/- 104 vs. 1,080 +/- 98 s; P < 0.01) from pre- to postaltitude. Living at 2,500 m and training at lower altitudes for 24 days increases Hbmass and RCV. These changes may contribute to enhance performance of elite endurance athletes.

To study the potential influence of long-term, high-intensity physical training on premature osteoarthrosis of the ankle joint, we re-examined former members of the Swiss National team from 1973 in retrospective cohort study in 1988. Twenty-seven track and field long-distance runners and orienteers (mean age 42 [95% confidence interval 41-43] years), 9 bobsledders (42 [39-46] years) and a control group of 23 healthy normal men (35 [33-36] years) were investigated. Physiological and exercise characteristics of all subjects had been recorded in 1973, and in 1988 these measurements were repeated together with a rheumatological and radiological examination of the ankle joint. A four-point scale of radiological joint state was used, taking into account the degree of subchondral sclerosis, osteophyte formation and joint space narrowing. In univariate analysis, the long-distance runners, and among them especially the orienteers (n = 10), showed significantly (both p less than 0.05) more radiological signs of degenerative ankle disease than controls. After adjustment for age, this difference disappeared. Age was itself significantly and positively related to radiological degenerative ankle disease (r less than 0.38; p less than 0.01). Orienteers reported significantly more frequently (60 vs 12%; p less than 0,01) functional instability of the ankle joint than track and field runners. Functional and mechanical (clinical) instability were interrelated in our material (r = 0.33; p less than 0.05) but neither of them was significantly related to radiological signs of degenerative ankle disease.(ABSTRACT TRUNCATED AT 250 WORDS)