ESPEN Congress Geneva 2014DIETETIC SESSION: SPORT AND NUTRITION

Nutrition in the extreme environment: translating top physical experiences into clinical practiceP. Bärtsch (DE)

Innere Medizin VII / Sportmedizin

Nutrition in extreme environment:Translating top physical activity

into clinical practice

Peter Bärtsch

Ethical dilemmasBioethical principlesApplication of bioethical

principles to “Nutrition at the end-of-life”

The decision-making process

• Acute exposure (AMS)

• Chronic exposure: level altitude

Aussicht CRM

• headache• loss of appetite

nausea• dizziness• insomnia• peripheral edeme

Acute Mountain Sickness (AMS)

• severe headache• vomiting

Characteristics of AMS

• Manifestation starting at 2000 - 2500 m

• Delayed onset of 4 - 24 hours

• Maximum on day 2 - 3, usually most prominent after the first night at a new altitude

• Clinical course: - spontaneous recovery in 1 - 2 days- rarely progression to HACE

• Prevalence depending on: - altitude - susceptibility - rate of ascent - acclimatization - fitnessBärtsch P and Swenson E, NEJM 2013

Prevention of AMS by carbohydrate rich diet?

• Rationale:metabolization of glycogen → greater CO2-production at a given O2-consumption → Ventilation ↑ → PaO2/SaO2 ↑

• Effect of 1 g sucrose/kg BW on SaO2:after 30 min at 12,8% O2 (≈ 3500 m) → 4% SaO2↑

(P. Golja, HAMB 2009)

• Effect on AMS questionable, largest study negative:- 68 % vs 45 % carbohydrates over 4 days - 8 hours at 10 % (FIO2 5500 m), n= 19- AMS score not different between groups - SaO2 not different between gourps

Swenson ER, Aviat Space Environ Med 1997

15:00 24:00 16:00 24:00 6:00 24:00 6:00

Day 1 Day 2 Day 3 Day 4

HA 1 HA 2 HA 3

1190m

3320m

3611m

4559m 4559m

5h

1,5h

4h

AMS score 1.2 4.5 2.0Correlation ns r = - 0.47 ns

- hunger↓ desire to eat↓- liking of fat and savory↓- liking of sweet =

No association with plasma levels of:- glucagon- CCK- PYY- amylin

Aeberli I, Eur J Nutr 2012

Ad libitum meal at 446 m and at 4559 m

(n=11)

Increased leptin with loss of appetite at 4559 m

Tschöp M., Lancet 1998

Viewpoint: Sierra-Johnson, JAP 2008

Role for Grehlin?Data controversial

• Increased demand - higher resting metabolic rate (Butterfield, JAP 1992) - possibly increased physical activity

• No malabsorption for- xylose 4800m: Chesner, Postgrad Med J1987- fat 4800m: Chesner, Postgrad Med J 1987- protein 5000m: Kayser, JAP 1992

• 4 % of the ingested calories at 5000 m in feces (Kayser, JAP 1992)

→ if appetite normal and food palatable: ± constant weight

Body weight with prolonged stay at 4300 – 5000 m

Body weight with prolonged stay at 4300 – 5000 m

intake = (7 d) intake ↑ (14 d)

- 200 g - 70 g per day

Pikes Peak 4300 m

study ´92 study ´93

- 90 g - 96 g - 1.9 kg - 2.0 kg (50% fat) (mostly water?)

Lobuche 5000 m

Butterfield, JAP 1992 Kayser, JAP 1992 and IJSM 1993

Silverhut 1961, 5800 m

Body weight at extreme altitude ( > 5000 m)

On Makalu 7400 m

Ward, Milledge and West: High Altitude Medicine Physiology, 1995

Views on diets (not only at altitude) are

strongly held, often the strength of

opinion being inversely related to the

strength of scientific evidence.

High Altitude Medicine and Physiology;Ward, Milledge, West (Chapman and Hall, 1994)

West JB: High Altitude Medicine Physiology, Taylor & Francis 2013

Weight Loss at 5800 m

6

647 g/day

Base camp at 4500 m

1

0

-1

-2

-3

-4

-5

-6

kg

Weight Loss with Operation Everest III (COMEX)

174 g/day

Richalet JP, High Alt Med Biol 2010

Weight loss at various altitudes

Altitude Weight loss (g/d) (total kg)

14 d at 4300 m 70 g 1.3 kg Butterfield, JAP 1992

21 d at 5000 m 90 g 1.9 kg (50 % fat) Kayser, JAP 1992

21 days at 6542 m 233 g 4.9 kg (74 % fat) Westerterp, JAP 1994

AMREE - to 5400m (BC),(25 d) 76 g 1.9 kg (71 % fat)- above 5400m (47 d) 85 g 4.0 kg (27 % fat) Boyer, JAP 1984

OE II to 8848 in 40 d 185 g 7.4 kg (33 % fat) Rose, JAP 1988

OEIII to 8848 in 31 d 174 g 5.4 kg (75 % fat) Westerterp, JAP 2000

Everest BC in 37 d 86 g 3.2 kg Reynolds, J Nutr 1998

Everest climbers in 37 d 197 g 7.3 kg (mostly fat)

Energy deficit above 5000 m

• 24% in 6452 m (field study, n=10, little exercise) Average daily metabolic rate 2820 Kcal

(Westerterp, JAP 1994)

• 45% in 5300 - 8400 m (field study, n=5): Average daily metabolic rate 3250 Kcal, on Mt. Blanc 3500 Kcal

(Westerterp, JAP 1992)

• 43% bei OE II (chamber study, n = 7): Average daily metabolic rate 3146Kcal

(Rose, JAP 1988)

Possible causes for weight loss at extreme altitudes

• Increased energy requirements: resting metabolic rate, thermogenesis (cold environment), exercise

• Dehydration

• Acute mountain sickness

• Lack of palatable food

• Minor malabsorption possible: data inconsistent

• Reduction of appetite by severe hypoxia

1

0

-1

-2

-3

-4

-5

-6

kg

Weight Loss with Operation Everest III (COMEX)

174 g/day

Richalet JP, High Alt Med Biol 2010

Energy intake and energy expenditure at each altitude

Westerterp-Plantenga, JAP 1999

• No influence of fluid balance

• Switch to nibbling pattern

• Influence of AMS at 7000 and 8000m

Energiy deficit: - 5000 m: 10% - 6000 m: 21% - 7000 m: 38% 43% - 8000 m: 49%

Hunger and satiety during Operation Everest III

No studies that look into the mechanisms regulating appetite in acclimatized mountaineers above 5000m

Daily energy requirement of an Tour de France Cyclist

F. Brouns, Ehrnährungsbedürfnisse von Sportlern, Springer 1993

S-N traverse of Anapurna over 6 days by N. Joos and E. Loretan, 1984

260 Kcal 260 Kcal

Energy intake in the 2 days crossing from the East peak to the main peak (± always ≥ 8000 m)

+ about 3 liters fluid

Steinbach-Tranutzer K, Reihe Bergabenteuer: Norbert Joos, AS Verlag Zürich, 2008, p 82

→ 8000 m: VO2max is 65 % ↓

Reduction of VO2max with altitude

Per 100 m above 1500 m decrease of VO2max by 1 %

Fulco CS, Aviat Space Environ Med 1998

• Avoid AMS by adjusting ascent rate to individual altitude tolerance

• Eat what you like most, as often and as much as you can

• What works on long alpine tours also works on 8000 m peaks

• Logisitc aspects: weight and fuel consumption → dehydrated food: water used for cooking drinkable

Recommendations for climbing 8000 m peaks

Nutrition in the mountains

Eat what you like and take your time - also at extreme altitudes

F. Brouns, 1993 Rheinwaldhorn 1983

• Mechanisms of loss of appetite not identified, significant effects above 4000 m, this altitude not suitable for obese individuals as at 4500 m: - PaO2 40 – 50 mmHg

- SaO2 75 – 85 % - periodic breathing during sleep

• Hypoxia induces low grad inflammation, effect on adipose tissue?

• Modalities: - living in hypoxia? (→ trekking) - sleeping in hypoxia (tents) - training in hypoxia (reduced intensity)

• No convincing studies

Rationale for treatment of obesity by hypoxia