Table 1A.
Authors | Participants M/F, Age [years] |
Type of exposure |
Diet manipulation |
Altitude level [m] |
Duration [days] |
Body weight [Δkg (Δ% of BW)] |
Body composition [Δkg (Δ%)] |
||||
---|---|---|---|---|---|---|---|---|---|---|---|
Passive | Active | Yes/No | FFM | FM | MM | TBW | |||||
Moderate altitude | |||||||||||
Ocobock (2017) | 18-31 yrs G1(temperate): 37 M G2(cold): 22 M G3(temperate): 16 F G4 (cold): 6 F |
Endurance Temperate Cold Temperate Cold |
No (recordings) |
3205-3658 | 84; G1: 112; G2: 84; G3: 112; G4: |
–2.8 (–3.6) –2.3 (–3.0) –1.1 (–1.6) –2.1 (–3.0) |
–1.9 (–21.0) –0.8 (–9.6) –1.6 (–9.5) –2.6 (–14.6) |
–0.9 (–1.4) –1.5 (–2.3) 0.5 (1.0) ns 0.6 (+1.2) |
|||
Jacobs et al. (2016) | 8 M, 1 F 26.9 ± 3.7 yrs |
Sea level activity | No | 3454 | 28 | ↔ | ↔ | ↔ | |||
Mekjavic et al. (2016) | 11 M 23.7 ± 4.0 yrs |
Stay at simulated altitude | No (recordings, ad libitum) |
2800 3000 3200 3400 |
(10) 2 2 3 3 |
–0.9 (–1.2) ns | –0.8 (–1.3) ns | –0.1 (–0.9) ns | |||
Kasprzak et al. (2015) | 9 M 28.0 ± 4.3 yrs |
Ascents | No (dietary recordings, ad libitum) |
3200 up to 3800 | 14 | –1.6 (–2.2) | –1.1 (–1.9) ns | –0.5 (–4.0) ns | –0.7 (–1.5) ns | ||
Chia et al. (2013) | 10 M 14.9 ± 0.4 yrs |
Daily Swimming | No | 2300 | 21 | 0.1 (0.1) ns | 0.8 (+1.5) | –1.7 (–11.4) | |||
Chen et al. (2010) | 12 M 31 ± 1.1 yrs |
Daily hiking | No (ad libitum) |
between 2200 and 3800 | 25 | –1.4 (–2.0) ns | –2.1 (–15.3) | ||||
Lippl et al. (2010) | 20 M 55.7 ± 4 yrs |
Stay at natural altitude | No (no diet restrictions) |
2650 | 7 | –1.5 (–1.4) | na (–0.3) ns | na (0.1) ns | |||
Greie et al. (2006) | 36 M 56 yrs (36-66 yrs) |
12 hiking sessions | No (standardized nutrition menues, no dietary restrictions) |
1700+ | 21 | –3.3 (∼-3.3) | |||||
Gunga et al. (2003) | 22 M 54 yrs (40-64 yrs) |
Hiking and swimming | No (ad libitum) |
∼1700 | 21 | –0.4 (–0.4) | 1.6 (2.4) ns | 0.6 (1.2) | |||
Tanner and Stager (1998) | 5 M 40.0 ± 5.5 yrs |
Trekking | No (Dietary recordings, no attempt to manipulate diet, goal: 5500 kcal/day) |
2200-4300 | 21 | –4.2 (–5.4) | –3.1 (–4.7) | –1.0 (–8.2) | |||
Hoyt et al. (1994) | 6 M 31 ± 4 yrs |
Strenuous winter exercise | Yes (prescribed diet, US military field ration (22.7 MJ/d) dietary records) |
2500-3100 | 5 | –1.8 (–2.3) | –0.4 (–0.6) ns | –1.4 (na) | –0.1 (–0.2) ns | ||
Schena et al. (1992) | 11 M, 5 F 35.8 ± 5.6 yrs G1: dietary supplementation G2 placebo |
Trekking | Yes (dietary recordings, amino acid supplementation) |
2500-4000 (4 d < 3000) |
21; G1 21; G2 |
–1.0 (–1.6) –1.8 (–2.8) |
0.7 (1.5) ns –0.2 (–0.4) ns |
–1.8 (–11.8) –1.6 (–10.2) |
|||
Greenleaf et al. (1978) | 6 M 21-23 yrs G1: n = 3 G2: n = 3 |
Running (2 × 30 min/day) simulated altitude | Yes controlled diet (3309 kcal/day)G1 with fluid replacement G2 drank ad libitum |
2287 | 8 | –0.6 (–0.9) |
Studies presented in square brackets are not included in the meta-analysis due to missing data. M, male; F, female; yrs, years (mean ± SD or min-max) d, days; ns, non-significant; n.a., no data available; Δkg, mean changes in BW, FFM, FM, MM and TBW before and after data collection or mean changes over a defined period; Δ%, mean change in percent compared to baseline or to a defined period; BW, bodyweight; FFM, fat free mass; FM, fat mass; MM, muscle mass; TBW, total body water; G, study groups. If no data were available but direction of change was illustrated, arrow is indicated: ↔ no change.