Supplementation assists mountain climbers at high altitudes

Polish researchers analyzed the dietary habits, supplementation and nutritional value of diets of high mountain climbers. The study revealed that most climbers did not meet their energy needs with diet. However, that could be altered with an increase in carbohydrates, protein and vitamins, the researchers suggested.

“Supplementation has also been shown to influence muscle protein synthesis, especially in conditions such as immobilization and energy restriction, or when consumed with other nutrients,” the scientists wrote. “Substances with antioxidant activity, e.g., vitamin C, α-tocopherol and α-lipoic acid, have a modulating effect on oxidative stress and [acute mountain sickness] symptoms at high altitudes.”

Energy expenditure​

The study group involved 28 men from Poland between 23 and 42 years old. They were taking part in summer mountaineering expeditions in Peru and Pakistan and were at altitudes greater than 3,000 meters above sea level for at minimum of three weeks.

Before participating in the project, the climbers consulted with a sports medicine doctor and took ECG, blood and urine tests. The researchers logged anthropometric data and BMI of the group. Any presence of chronic diseases and age over 45 were disqualifying factors from participating in the project.

The analysis of dietary habits and attitudes was also based on responses to a 54-part questionnaire divided into three sections which included the following: mountain experience and climbing experience, as well as health status and emerging ailments in the high mountains and after returning from the mountains; preparation for the expedition related to health analysis; and eating behavior during the mountain action (including preferred foods, supplements, liquids, frequency of consumption of food groups in the mountains, appetite). 

Fifteen of the climbers kept food diaries from three days of the expedition while climbing. The macronutrient content of the diet was assessed.

The researchers also measured energy expenditure using a monitor recording heart rate, the Polar M430, which recorded 24/7 for three active days. Pulsometers consisted of watches (receiver) and straps with transmitters (Polar H10 sensor) were used.

“Our study revealed that most climbers did not meet their energy needs with diet,” the researchers wrote. “Increased energy expenditure during long high-altitude hikes may be responsible for a negative energy balance leading to changes in body composition, namely loss of fat mass and lean body mass.” 

Study participants were less likely to consume vegetables, fruits, eggs, milk and milk products, butter and cream, fish and meat. 

“Inadequate supply of energy and protein, which is the cause of the loss of lean body mass, has a negative effect on aerobic capacity, muscle strength and immunity,” the researchers added.

A dietary imbalance​

However, climbers detailed to what extent they used supplements, including caffeine, which was the most used in the survey.

Caffeine influences cognitive and physical functions by blocking adenosine A1 and A2a receptors in the central nervous system and peripheral tissues, the scientists said. Doses of 1–4 mg/kg body weight improve alertness, concentration, and reaction time, while doses of 3–6 mg/kg bw caffeine can enhance cognitive performance, motor skills, and physical performance in many types of sports.

“These features are especially important in technically demanding places when climbing and when descending mountains or rappelling,” the researchers wrote.

As for omega-3 fatty acids, there’s a positive association between supplementation and reaction time, skeletal muscle recovery, inflammatory markers and cardiovascular dynamics, according to the scientists. Supplementation has also been shown to influence muscle protein synthesis, especially in conditions such as immobilization and energy restriction, or when consumed with other nutrients.

The climbers also took a protein supplement rich in leucine to protect the body against the reduction of lean body mass at high altitude.

Despite these interventions, the climbers’ diet was low in calories, the protein supply was low and the fat supply was too high, the researchers noted.

“The climbers’ diet was low in calories, the protein supply was too low, and the fat supply was too high,” the scientists wrote. “There is a need to develop nutritional and supplementation recommendations that would serve as guidelines for climbers, improving their well-being and exercise capacity in severe high-mountain conditions, which would take their individual taste preferences into account.”

Journal: Nutrients​ 

https://www.mdpi.com/2072-6643/15/19/4219​

Diet, Supplementation and Nutritional Habits of Climbers in High Mountain Conditions​

Authors: Ewa Karpęcka-Gałka et. al.