Performance and thermoregulation of Dutch Olympic and Paralympic athletes exercising in the heat: Rationale and design of the Thermo Tokyo study: The journal Temperature toolbox

Figures & data

Figure 1. Flow chart of the Thermo Tokyo study design Personalized. DXA, dual-energy X-ray absorptiometry; ISAK, International Society for the Advancement of Kinanthropometry; MRI, magnetic resonance imaging; RH, relative humidity

Figure 2. Overview of the Thermo Tokyo personalized exercise test protocol. After 5 min seated rest (Baseline), athletes will start to exercise at 100 W (ergometer) or 30–70 W (hand ergometer). After 3 min, the initial workload will be gradually adjusted to reach 70% of the athlete’s maximal heart rate. After 20 min, workload will gradually be increased every 3 min with 5% until volitional exhaustion. After exercise cessation, participants will have a 3 min cool-down at a self-selected wattage followed by 10 min seated rest. Gastrointestinal temperature (T_gi), skin temperature (T_sk), heart rate (HR), and exercise performance will be examined continuously throughout the protocol. Participant’s body mass will be measured at baseline and directly after finishing the experimental protocol to determine whole body sweat rate (WBSR). Perceptual outcomes will be scored at baseline, every 5 min during the warm-up phase and every 3 min during the incremental phase. The personalized exercise protocol (i.e. changes in workload over time) obtained during the control condition (T_ambient 15°C, RH 50%) will subsequently be applied to the second exercise test in simulated Tokyo conditions (T_ambient 32°C, RH 75%)

Table 1. Personalized input parameters for the Fiala-thermal-Physiology-and-Comfort (FPC) simulation model

Simulation model category	Input variables
Active system	Acclimatization (days); VO2max (ml/kg/min)
Passive system	Height (cm); Weight (kg); Age (years); Sex (unisex/M/F); Body Fat Percentage (%)
Anthropometry	Cervical height (cm); Omphalion (waist) height (cm); Crotch height (cm); Knee height (cm); Head length (cm); Head width (cm); Menton-head top height (cm); Shoulder width (cm); Upper arm length (cm); Lower arm length (cm); Hand length (cm); Hand width (cm); Foot height (cm); Foot length (cm); Foot width (cm); Head circumference (cm); Neck circumference (cm); Chest circumference (cm); Waist circumference (cm); Buttock circumference (cm); Axillary arm circumference (cm); Forearm circumference (cm); Thigh circumference (cm); Calf circumference (cm)

M, male; F, female

Figure 3. Example of a processed 3D scan

Table 2. Different environmental conditions for the Fiala-thermal-Physiology-and-Comfort (FPC) simulation model

Simulations	Tambient (°C)	RH (%)	Vair (m/s)	Rad (W/m^2)	Accl days
Baseline	32	75	0.2	0	0
Higher temp	38	75	0.2	0	0
Lower temp	26	75	0.2	0	0
Higher RH	32	90	0.2	0	0
Lower RH	32	60	0.2	0	0
Acclimatized	32	75	0.2	0	10
Radiation	32	75	0.2	921	0
Worst case	37.5	79	0.2	921	0
Best case	26.1	39	0.2	0	0

T_ambient, ambient temperature; RH, relative humidity; V_air, air flow; Rad, radiation; W, watt; Accl days, acclimation days

Table 3. Data catalog table of the Thermo Tokyo study. Data is available for reuse upon reasonable request via the corresponding author

Category	Sub category	Variables
General	Personal info	Age (years); Sex (unisex/M/F); Type of sport; Sport discipline*; Type of injury**; Regular menstrual cycle (yes/no); Date last menstrual period (yyyy-mm-dd); Training >25°C past 4 weeks (yes/no); Consecutive training days >25°C
	Anthropometry	Height (cm); Weight (kg); Body mass index (kg/m^2); Body surface area (m^2)***
Exercise test	Workload & performance	Peak power output (W); Peak power output (W/kg); Workload (W) over time (min); Time to exhaustion (min); Relative change in time to exhaustion (%); Relative change in peak power output (%)
	Physiological outcomes	Resting HR (bpm); Exercise-induced increase in HR (bpm); Peak HR (bpm); HR (bpm) over time (min); Resting Tgi (°C); Exercise-induced increase in Tgi (°C); Peak Tgi (°C); Tgi (°C) over time (min); Resting Tskin (°C); Exercise-induced increase in Tskin (°C); Peak Tskin (°C); Tskin (°C) over time (min); Total fluid intake on study visit day (L); Whole body sweat loss (L); Whole body sweat rate (L/h); Dehydration (%)
	Perceptual outcomes	Resting thermal sensation (au); Peak thermal sensation (au); Thermal sensation (au) over time****; Resting thermal comfort (au); Peak thermal comfort (au); Thermal comfort (au) over time****; Resting RPE (au); Peak RPE (au); RPE (au) over time****
	Environmental conditions	Ambient temperature (°C); Relative humidity (%); Wet bulb globe temperature (°C)
Anthropometrics (ISAK)	Anthropometry	Height (cm); Weight (kg); Body mass index (kg/m^2); Body surface area (m^2)**; Arm circumference relaxed (cm); Arm circumference flexed and tensed (cm); Waist circumference (cm); Gluteal circumference (cm); Calf circumference (cm); Epicondyle humerus width (cm); Epicondyle femur width (cm)
	Skinfolds	Triceps skinfold (mm); Subscapular skinfold (mm); Biceps skinfold (mm); Iliac crest skinfold (mm); Supraspinal skinfold (mm); Abdominal skinfold (mm); Front thigh skinfold (mm); Medial calf skinfold (mm); Total skinfold (mm)
DXA scan	Fat mass	Fat mass L arm (g); Fat mass R arm (g); Fat mass trunk (g); Fat mass L leg (g); Fat mass R leg (g); Fat mass head (g); Total body fat mass (g); Total body fat percentage (%)
	Lean mass	Lean mass L arm (g); Lean mass R arm (g); Lean mass trunk (g); Lean mass L leg (g); Lean mass R leg (g); Lean mass head (g); Total body Lean mass (g)
	Bone mineral content (BMC)	BMC L arm (g); BMC R arm (g); BMC trunk (g); BMC L leg (g); BMC R leg (g); BMC head (g); Total BMC (g)
3D scan	Anthropometry	Height (cm); Body surface area (m^2); Cervical height (cm); Omphalion (waist) height (cm); Crotch height (cm); Knee height (cm); Head length (cm); Head breadth (cm); Menton-head top height (cm); Biacromial (shoulder) breadth (cm); Acromion-radiale (upper arm) length (cm); Radiale-stylion (lower arm) length (cm); Hand length (cm); Hand breadth (cm); Foot height (cm); Foot length (cm); Foot breadth (cm); Head circumference (cm); Neck circumference (cm); Chest circumference (cm); Waist circumference (cm); Buttock circumference (cm); Axillary arm circumference (cm); Forearm circumference (cm); Thigh circumference (cm); Calf circumference (cm)

au, arbitrary units; BMC, bone mineral content; bpm, beats per minute, F, female; HR, heart rate; L, left; M, male; R, right; RPE, rating of perceived exertion; T_gi, gastrointestinal temperature; T_skin, skin temperature; W, watt. *classification of types of sports into skill, power, mixed and endurance disciplines, based on the relative isometric and isotonic components of the exercise training. **in case of Paralympic athlete ***Calculated using the Dubois formula. ****Perceptual outcomes will be scored at baseline, every 5 min during the warm-up phase, every 3 min during the incremental phase and every 5 min during the recovery phase.