Table 1B.
Authors | Participants M/F, Age [years] |
Type of exposure |
Diet manipulation |
Altitude level [m] |
Duration [days/wk] |
Body weight [Δkg (Δ% of BW)] |
Body composition [Δkg (Δ%)] |
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---|---|---|---|---|---|---|---|---|---|---|---|
Passive | Active | Yes/No | FFM | FM | MM | TBW | |||||
High altitude | |||||||||||
Beidleman et al. (2017) | 12 M, 5 F 22.9 ± 1.5 yrs |
Several 2-3 mile hikes above 3500 m | No (ad libitum) |
4300 | 12 | –3.0 (-4.0) | |||||
Berryman et al. (2017) | G1(standard protein): 8 M 23.1 ± 3.3 yrs G2 (higher protein diet): 9 M 23.7 ± 7.3 yrs |
low-moderate | Yes (both groups were subjected to a 40% energy deficit) |
4300 | 21; G1 21; G2 |
–7.2 (-8.3) –7.1 (-8.9) |
–4.0 (-6.3) –3.3 (-5.6) |
–3.3 (-16.5) –3.9 (-22.5) |
|||
Tam et al. (2016) | 7 F 36.3 ± 7.1 yrs |
Moderate intensity |
No | 598 4132 |
12 14 |
–0.6 (-0.9) ns 1.2 (-1.9) ns |
–1.9 (-4.0) ns +0.5 (1.1) ns |
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Debevec et al. (2014a) | 11 M 27 ± 6 yrs |
a): bed rest c):bed rest (simulated altitude) |
b): low-moderate (simulated altitude) |
Yes (individ. tailored, strictly controlled, standardized diet) | 3 different conditions 1: normoxia 2: 4300 3: 4300 |
21; a) 21; b) 21; c) |
na (-3) na (-4) na (-5) |
na (-4) na (-5) na (-5) |
na (↔) na (↔) |
||
Debevec et al. (2014b) | 11 M 24 ± 2 yrs a) b) c) |
a):bed rest c).:bed rest |
b):low-mod. | Yes (individually tailored, controlled, standardized diet) |
3 different conditions a) normoxia b) 4000 c) 4000 |
10; a): 10; b) 10; c) |
–1.4 (-2.0) –1.5 (-2.1) –2.0 (-2.8) |
–2.4 (-4.3) –2.1 (-3.8) –2.1 (-3.8) |
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Subudhi et al. (2014) | 16 M 20.8 ± 1.4 |
Physically active | No | 5260 | 16 d | –2.4 (-3.4) | –2.1 (-4.9) | –1.4 (-15.0) | |||
Wing-Gaia et al. (2014) | 10 M, 8 F 44.5 ± 10.4 yrs (G1+G2) G1: N = 10, (leucine supplementation) G2: N = 8, (control) |
Trekking | Yes (dietary recording, leucine supplementation) |
4140 (2835-5364) 1 d < 3000 |
13; G(1+2): 13; G1: 13; G2: |
–1.9 (-2.2) na (-2.2) na (-2.3) |
–1.0 (-1.7) na (-1.2) na (-2.1) |
–0.8 (-4.0) na (-5.4) na (-2.9) |
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Boos et al. (2014) | 33 M, 14 F 34.5 ± 9.3 yrs |
Graduated ascent, start at 3600 m |
No |
3833 4450 5129 |
10 |
0.5 (0.7) 0.1 (0.1) 0.9 (1.2) |
|||||
[De Mol et al. (2012)] | 8 M, 5 F 48.2 ± 9.7 yrs |
Trekking expedition | No | 4167 | 12 | (na) ↔ | |||||
Levett et al. (2012)∗ | G1: staff, 3 M, 3 F 39.5 ± 12.4 (G2: climber) 11 M, 1 F 38.0 ± 4.9 |
Ascent/stay ascents |
No | 1300-5300 up to 6400-8848 |
G1: 13 ascent/6 stay G2: 66 |
–0.9 (-1.2) ns –9.6 (-11.7)# |
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Ermolao et al. (2011) | 12 F 21. 5 ± 3.1 yrs |
5 d ascent+ aerobic/strength moderate/intense exercise |
No | 5050 | 21 | –1.0 (-1.6) ns | –0.4 (-0.9) ns | –0.7 (-4.1) ns | –0.2 (-1.3) ns | ||
Smith et al. (2011) | 7 M, 3 F 37 ± 9 yrs (26-49 yrs) |
Expedition | No | 353-4000 4000-4750 4750-5300 |
after 3 d after 6 d after 9 d |
–1.4 (-2.0) ns –1.4 (-2.0) –3.1 (-4.5) |
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Ge et al. (2010) | 160 M 32 ± 6 yrs G1: N = 85 (sea level residents) G2: N = 35 moderate altitude (altitude residents) |
Construction work 5 h/d | No | 4678 | 33; G1: 33; G2: |
–7.1 (-10.6) –1.4 (-2.2) |
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Holm et al. (2010) | 9 M 24-30 yrs |
Stay at natural altitude | Yes (registered food intake, matched amount of food as during sea level, similar diet as at sea level) |
4559 | 7-9 | –0.4 (-0.5) ns | –0.1 (-0.2) ns | –0.2 (-1.5) ns | |||
Mizuno et al. (2008)∗ | 15 M 25-45 yrs G1: N = 7 G2: N = 8 |
G1:little walking (base camp) G2:climbing/ ascents |
No | 5250 5250 up to 6400-7500# |
75; G1: 75; G2: |
–7.7 (-10.1) –5.4 (-7.1) |
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Vats et al. (2007) | G1:placebo 10 M 23.8 ± 3.6 yrs G2:supplement (NAC) 10 M 22.5 ± 1.9 yrs G3:supplement (Vit E) 10 M 22.4 ± 1.9 yrs |
Stay 3600 (+exercise), ascend to 4580 | Yes (N-acetyl cysteine/vitamin E supplementation) |
HA:3600 HA:4580 HA:3600 HA:4580 HA:3600 HA:4580 |
7, G1: 2, G1: 7, G2: 2, G2 7, G3: 2, G3: |
–2.7 (-4.4) –3.1 (-5.0) –1.8 (-2.8) –2.3 (-3.6) –1.6 (-2.6) –2.1 (-3.4) |
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Barnholt et al. (2006) | (adequately fed) 7 M 21.3 ± 2.8 yrs |
Stay at natural altitude | Yes (prescribed, increased caloric intake) |
4300 | 21 baseline - d 21 |
–0.8 (-1.1) ns | –1.4 (-2.1) | 0.5 (7.4) ns | |||
Fulco et al. (2005) | 16 M G1 (n = 8): 25.1 ± 6 yrs G2 (n = 8): 25.3 ± 6 yrs |
Increased energy expenditure by 30-40% (∼ 4,567 kcal/day, e.g., running, hiking | Yes, standardized, diet individualized amounts (but voluntary reduced by ∼750 kcal/day versus sea level) |
4300 | 10 | –2.3 (-3.0) | |||||
Shukla et al. (2005) | 30 M 23.3 ± 2.5 yrs |
Stay at natural altitude | No | 3600 4300 |
2 7 |
–2.12 (-3.3) | |||||
Lundby et al. (2004) | 6 M, 2 F 25 ± 8 yrs |
sea level activity | No | 4100 | 56 | –1.0 (-1.3) ns | |||||
Fulco et al. (2002) | G1: 10 M 22.6 ± 4 yrs G2: 7 M 21.1 ± 3 yrs |
Program of strenuous exercise (cycle ergometry, treadmill walking, and weight lifting) | Yes, G1: energy deficit by ∼1500 kcal/day G2: adequate kcal/day to maintain BW |
4300 |
21; G1: 21; G2: |
–6.6 (-8.2) –1.0 (-1.3) ns |
–4.6 (-6.5) –0.8 (-1.2) ns |
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Mawson et al. (2000) | 16 F 21.7 ± 0.5 yrs |
Treadmill, ergometer, strength training | Yes (controlled diet, specified quantities of standardized diet; increased energy intake) |
4300 | 12 | 0.41 (0.7) ns | |||||
Westerterp-Plantenga et al. (1999)∗ | 8 M 26.0 ± 2 yrs |
Stay at simulated altitude | No (ad libitum) |
5000 6000 7000 8000 |
d2–d6 d9–d12 d15–d19 d26–d28 |
–2.0 (-2.7) –2.8 (-3.8)# –3.6 (-4.8)# –4.7 (-6.3)# |
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Braun et al. (1998) | 16 F 21.7 ± 2.0 yrs |
Stay at natural altitude | Yes (standardized diet, daily adjusted energy content to maintain body weight) |
4300 | 12 | –0.5 (-0.8) ns | |||||
Armellini et al. (1997) | 8 M, 2 F 28-49 yrs |
Climbing/trekking | No | >4500 | 16 | –3.3 (-4.7) | –1.2 (-2.2) | –2.2 (-14.7) | |||
Beidleman et al. (1997) | 6 M 31 ± 2 yrs |
Stay at natural altitude | No (free access to fluid and food) |
4300 | 16 | –1.6 (-1.9) | |||||
Kamimori et al. (1995) | 8 M 28.2 ± 3.1 yrs |
Stay at natural altitude | No | 4300 | 16 | –4.9 (-5.9) | –1.2 (-8.0) | ||||
Savourey et al. (1994)∗ | 6 M, 1 F 35.0 ± 1.7 yrs |
Stay + ascents | No | 4350 (3 ascents to 4807) |
7 | –0.7 (-1.0) ns | –0.4 (-4.1) ns | ||||
Kayser et al. (1993) | 8 M 33.7 ± 4.6 yrs |
Stay at natural altitude | No (free access) |
5050 5050 5050 |
7 14 28 |
–0.3 (-0.4) ns –2.7 (-3.5) –2.6 (-3.4) |
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Butterfield et al. (1992) | 7 M 23.7 ± 4.3 yrs (increased energy intake) |
Sea level activity | Yes (prescribed and controlled food intake, increased energy intake from day 8, adjusted according to increased BMR) |
4300 | 21 d 1- d 7 d 8- d 21 |
–2.1 (-2.9) –1.3 (-1.8) –0.9 (-1.2) |
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Fulco et al. (1992) | 16 M 27.7 (23-35) yrs |
Technical climbing, hiking (4 out of 16 days) | No | 3700-4300 | 16 | –5.9 (-7.0) | –2.4 (-3.5) | –3.5 (-24.3) | |||
Kayser et al. (1992) | 6 M 31.8 ± 4.5 yrs |
Stay at natural altitude |
No | 5000 | 21 | –1.9 (-2.7) | |||||
Wolfel et al. (1991) | 7 M 23 ± 2 yrs |
Stay at natural altitude | Yes (controlled food intake, sufficient to cover measured energy needs) |
4300 | 21 | –2.4 (-3.3) | |||||
Bradwell et al. (1986) | 19 M, 2 F 22-56 yrs G1 (acetazolamide) G2 (placebo) |
Expedition | No (unrestricted) |
1300-4846 4846 (5700) |
10 d ascent, 6 d stay (with 1 d to 5700 m n = 8) G1: G2: |
(na) ↓ (na) ↓ |
0.2 (8.0) 0.4 (18.0) |
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Fulco et al. (1985) | 8 M 21.5 ± 1 (18-28 yrs) |
Stay at natural altitude (relatively sedentary lifestyle) | No (ad libitum) |
4300 | 18 | –1.5 (-1.8) | –2.1 (-3.1) | + 0.6 ns (+4.3) | |||
Stock et al. (1978) | 4 M, 2 F 29-34 yrs |
Stay at natural altitude |
No | 3650 | 21 | –3.6 (-5.5) | |||||
Bharadwaj and Malhotra (1974) | 65 M 18-30 yrs |
Ascent/stay | Yes (increased caloric intake, 4600 kcal/d) |
227 to/stay at 3962-4115 | 8/28 | –0.6 (-1.1) | –1.3 (-2.5) | –0.44 (-6.8) | –1.1 (-2.8) | ||
Consolazio et al. (1972) | 11 M 19-25 yrs G1: N = 5 (normal nutrient distribution) G2: N = 6 (G2: high carbohydrate diet) |
Stay at natural altitude |
Yes (3740 kcal/d) |
4300 | 6; G1: 6; G2: |
–0.9 (n.a.) –1.1 (n.a.) |
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Jung et al. (1971) | 8 M G1: 4 M, 24.3 ± 9.2 yrs (age < 40 yrs) G2: 4 M, 55.8 ± 6.8 yrs (age > 40 yrs) |
Ascent | No | 3800 | 4; G1: 4, G2: |
–0.01 (-0,8) ns +0.05 (+3.8) ns |
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Dill et al. (1969) | 12 M 18-77 yrs |
Scheduled exercise tests, all-out climbs, varying voluntary activity | No | 3800 | 14 | –1.9 (-2.6) ns | |||||
Surks et al. (1966) | 5 M 19-23 yrs |
Stay at natural altitude |
Yes (prescribed diet, ∼2999 kcal/d) |
4302 | 8 | –2.5 (-3.5) | –0.7 (-1.2) ns | –1.7 (-10.4) | –0.5 (-1.2) ns |
∗Study displayed in high and extreme altitude table; 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; na, no data available; G, groups (only relevant groups from the individual studies are shown); Δkg, mean changes in BW, FFM, FM, MM and TBW before and after data collection or mean changes for 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. # data used for meta-analysis for extreme altitude only. If no data were available but direction of change was illustrated, arrows are indicated: ↔ no change, ↓ decrease; BMR basal metabolic rate.