Background: Energy expenditure may be difficult to assess when hiking difficult trails. Case presentation: We measured physical activity exercise energy expenditure (PAEE) directly from oxygen uptake using a mobile device (cardiopulmonary exercise testing, CPET), and by using a formula based on heart rate (HR), or metabolic equivalent values from the Compendium of Physical Activity, and other physiological outcomes. Outcomes and implications: Total PAEE (1342 kcal) using CPET showed a two-fold difference between ascending and descending (887 vs. 455 kcal) during a 124-min hike. For HR, PAEE was 1893kcal (+551 kcal overreporting), while compendium-based scenarios ranged from 1179 to 1446 kcal, which was in closer range (−163 to +104 kcal/min) compared to the CPET data. Fluid consumption was 1300 mL/hour, with 1.1% bodyweight loss, peak skin temperature of 35.2°C and core body temperature of 39.2°C. Recommendations: Tables reasonably predict energy expenditure while not precisely reflecting the actual situation.
AinsworthBEHaskellWLHerrmannSD, et al. (2011) 2011 Compendium of physical activities: A second update of codes and MET values. Medicine and Science in Sports and Exercise43(8): 1575–1581.
2.
AlhadadSBTanPMSLeeJKW (2019) Efficacy of heat mitigation strategies on core temperature and endurance exercise: A meta-analysis. Frontiers in Physiology10: 71.
3.
GuyerHGeorgescuMHondulaDM, et al. (2021) Identifying the need for locally-observed wet bulb globe temperature across outdoor athletic venues for current and future climates in a desert environment. Environmental Research Letters16(124042). Doi: https://doi.org/10.1088/1748-9326/ac32fb.
4.
HillsAPMokhtarNByrneNM (2014) Assessment of physical activity and energy expenditure: An overview of objective measures. Frontiers in Nutrition1: Article 5.
KeytelLRGoedeckeJHNoakesTD, et al. (2005) Prediction of energy expenditure from heart rate monitoring during submaximal exercise. Journal of Sports Sciences23(3): 289–297.
7.
LinsellJDPelhamECHondulaDM, et al. (2020) Hiking time trial performance in the heat with real-time observation of heat strain, hydration status and fluid intake behavior. International Journal of Environmental Research and Public Health17(11): 4086.
8.
NaldoRBoeckmanJVanosJK, et al. (2023) Short hydration education video and hiker fluid selection and consumption at trails, a non-randomized quasi-experimental field study. Nutrition and Health. Doi: https://doi.org/10.1177/02601060221150303.
9.
PériardJDRacinaisSSawkaMN (2015) Adaptations and mechanisms of human heat acclimation: Applications for competitive athletes and sports. Scandinavian Journal of Medicine & Science in Sports25(Suppl 1): 20–38.
10.
RiebeDEhremanJKLiguoriG, et al. (2018) ACSM’s Guidelines for Exercise Testing and Prescription (eds Deborah Riebe, JK Ehrman, Gary Liguori, et al.). Tenth Edit. Philadelphia: Wolters Kluwer. Doi: https://doi.org/10.1046/j.1523-5408.2001.00105.x.
11.
WardenaarFOrtega-SantosCPVentoK, et al. (2021a) Reliability of 3 urine specific gravity meters for measuring brix and urine solutions at different temperatures. Journal of Athletic Training56(4): 389–395.
12.
WardenaarFCOrtega-SantosCPVentoKAS, et al. (2021b) A 5-day heat acclimation program improves heat stress indicators while maintaining exercise capacity. Journal of Strength and Conditioning Research35(5): 1279–1286.
13.
WardenaarFCVentoKAOrtega-SantosCP, et al. (2022) The impact of different playing surfaces on physiological parameters in collegiate DI American football athletes. Volume 18, Issue 3. Doi: 10.1177/17479541221089748.
14.
WeirJ (1949) New methods for calculating metabolic rate with special reference to protein metabolism. The Journal of Physiology109(1–2): 1–9.
