Bc 148

Participants' body mass and height were determined in light clothing to the nearest 0.1 kg and 0.1 cm using electronic weighing scales and a stadiometer, respectively. Compartmental body composition was determined using bioelectrical impedance analysis (TANITA BC‐148), with participants holding an electrode in each hand whilst standing barefoot on two other electrodes. Participants were asked to consume 0.5 L of water 30 min before bioelectrical impedance assessments to standardize hydration status, having refrained from fluid consumption beforehand.

Participants first performed a single GXT to volitional exhaustion on a treadmill (Trakmaster TMX425CP; FullVision Inc., Kansas, USA) in a laboratory maintained within 18–20 °C to assess VO_2peak. Height and mass were measured using a stadiometer (SECA 213, Ecomed, NSW, Australia) and scales (BC-148, Tanita, Tokyo, Japan). The GXT commenced at 4.0 km h⁻¹ and increased by 1.0 km h⁻¹ every minute up to 8.0 km h⁻¹, then the speed was increased by 0.5 km h⁻¹ every minute. Treadmill gradient was fixed at 1% throughout testing to replicate oxygen costs associated with overground running (Jones and Doust 1996 (link)). Breath-by-breath respiratory gas was analysed via an online respiratory gas analyser (Metalyzer 3B; Cortex Biophysik GmbH, Leipzig, Germany) with a paediatric face mask (Hans Rudolph Inc., Kansas, USA). Volume and gas calibration were performed prior to each session as per manufacturer guidelines. HR was measured using a wireless chest-strap telemetry system (Polar Electro Oy, Kempele, Finland). Participants reported their RPE and affect prior to commencing the GXT and during the final 15 s of each minute. Testing was terminated when the participants were no longer able to maintain the required exercise intensity despite verbal encouragement.