ANTHROPOMETRIC AND CARDIORESPIRATORY ASSESSMENT IN AMATEUR CHILEAN TRAIL RUNNERS, THE PHYSIOLOGICAL BASIS FOR A HEALTHY LIFESTYLE

J. Enríquez-Schmidt¹, M. Monrroy-Uarac¹

¹Universidad Austral de Chile, Exercise Physiology Laboratory, Valdivia, Chile

Background: Trail Running has psychological, physical, and social benefits. Its recent growth has been exponential inside the running community and among people who wish to live a more active lifestyle, mainly because of natural environments, unique terrain features, and elevation changes. Although people of different fitness and ages practice it, performance components have only been evaluated in professional runners.

Purpose: To determine the anthropometric profile and cardiorespiratory function of amateur Chilean trail runners.

Methods: Analytical observational study. 41 male amateur trail runners (36.07 ± 6.37 years) were evaluated with a previously developed Trail Test. The International Society for Advancement of Kinanthropometry protocol was used for anthropometrical assessment (Rosscraft S.R.L Kit) determining BMI, muscle (Muscle%), fat mass percentages (Fat%), and somatotype. Cardiorespiratory measures were collected with breath-by-breath analysis (Jaeger Oxycon Mobile) using an average of 11 breaths and a 10-second recording time. Heart rate (HR) was measured with a Polar monitor and rate of perceived exertion (RPE) was obtained with the Original Borg Scale. Participants were instructed to achieve maximal effort. Maximal oxygen uptake (VO₂max) achieved when: 1) RPE ≥ 17, 2) Respiratory exchange ratio (RER) ≥ 1,1, 3) 95% of maximal theoretical HR, and 4) absolute oxygen uptake plateau (<150 ml/min differences) in spite of intensity increase. The first (VT1) and second (VT2) ventilatory thresholds were determined by two blind evaluators using the V-Slope method and the second non-linear increase in minute ventilation (V_E) and V_E versus carbon dioxide volume (VCO₂) accompanied by a concomitant non-linear increase in V_E/VCO_2, respectively. A descriptive statistical analysis was performed, and data are presented as mean ± standard deviation. Correlations were determined by Spearman’s Rho (p > 0.05) and Pearson (p > 0.01).

Results: BMI was 24.92 ± 2.86 kg/m2, Fat% 24.14 ± 3.74 and Muscle% 48.46 ± 3.16. Somatotype was categorized as endomesomorphic (3.50-5.23-1.84). Maximal HR was 177,39 ± 8,46 bpm, peak oxygen pulse 21,34 ± 2,96 ml/heartbeat, RER 1,16 ± 0,07, RPE was 17,93 ± 0,91, speed achieved 13,43 ± 0,73 km/h, inclination achieved 7,51 ± 1,5 %, and time to exertion was 7,28 ± 1,41 min. VO₂max was 50,29 ± 7,84 ml/kg/min. The VT1 was obtained at 32,55 ± 6,03 ml/kg/min and the VT2 at 45,26 ± 7,2 ml/kg/min, representing 64,72 and 90,00% of VO₂max respectively. Correlations between VO₂​​​​max and Fat% (-0.465) and Muscle% (0.353) were found.

Conclusions: Amateur trail runners elicit good to excellent cardiorespiratory function, good muscle%, and a healthy fat%. Correlations between cardiorespiratory fitness, Muscle%, and Fat% are weak but significant. VTs were achieved in lower oxygen uptake values but the same VO₂max percentage proportion as elite runners, representing an opportunity to assess and improve VT1 performance.

Implications: Trail is a positive sport for those who practice it, opening the possibility to enhance it as health prevention and treatment strategy.

Funding acknowledgements: No funding was provided for this investigation.

Keywords:
Running
Exercise test
Body composition

Topics:
Health promotion & wellbeing/healthy ageing/physical activity
Cardiorespiratory

Did this work require ethics approval? Yes

Institution: Valdivia Health Service

Committee: Scientific Ethics Committee Valdivia Health Service

Ethics number: 74