Clinical trial NCT05337111: Fitness and Fat Oxidation in Overweight Chinese, Indian and Malay Men
Official title: Differences in Cardiorespiratory Fitness and Fat Oxidation at Rest and During Exercise in Chinese, Indian and Malay Men With Elevated Body Mass Index.
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Overweight and Obesity
Lead sponsor: Nanyang Technological University
Sponsor class: OTHER
Collaborators: name: Ministry of Education, Singapore
First posted: 2022-04-20
Enrollment: 45
Sex: MALE
Minimum age (years): 21
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: CASE_ONLY
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Healthy but physically inactive Chinese, Indian and Malay men aged 21-45 years with an elevated body mass index for Asians.

Brief summary: South Asian men have lower cardiorespiratory fitness (CRF) than white men which is associated with a reduced capacity to oxidise fat during exercise. This is a risk factor for weight gain/regain. Whilst comparisons with Europeans are valuable, Asians are not a homogenous group and substantial differences in obesity and body fat partitioning exist with ethnicity. This cross-sectional pilot investigation aims to compare CRF and fat oxidation at rest and during exercise in Chinese, Indian and Malay men (from Singapore) with elevated BMI (23 -30 kg/m2). Forty-five men (15 each ethnicity) with elevated body mass index (23 -30 kg/m2) will complete testing in a fasted state on two separate mornings separated by ≥72 hours: (i) for a measure of CRF; and (ii) for a measure of fat oxidation at rest and during incremental exercise.

Detailed description: South Asian men have lower cardiorespiratory fitness (CRF) than white men which is associated with a reduced capacity to oxidise fat during exercise. This is a risk factor for weight gain/regain. Whilst comparisons with Europeans are valuable, Asians are not a homogenous group and substantial differences in obesity and body fat partitioning exist with ethnicity. This cross-sectional pilot investigation aims to compare CRF and fat oxidation at rest and during exercise in Chinese, Indian and Malay men (from Singapore) with elevated BMI (23 -30 kg/m2). Forty-five men (15 each ethnicity) with elevated body mass index (23 -30 kg/m2) will complete testing in a fasted state on two separate mornings separated by ≥72 hours: (i) for a measure of CRF; and (ii) for a measure of fat oxidation at rest and during incremental exercise. A submaximal exercise test will be used to estimate CRF (maximum oxygen uptake, VO2max) during walking using a standard protocol where subjects walk on a treadmill at 5 km/h with regular increments in gradient until individuals reach 80% of their estimated maximum heart rate \[220 - age (years)\]. Perceived exertion will be monitored assessed periodically during the test and expired gases continuously measured via a mouthpiece attached to an automated metabolic cart (Parvomedics MMS-2400; Parvomedics, Sandy, UT). Oxygen consumption will be extrapolated to estimate VO2max based on estimated maximum heart rate. Resting fat oxidation will be determined via a 30 minute measure of expired gases under a ventilated hood attached to an automated metabolic cart. Fat oxidation during exercise will be determined via walking on a treadmill with increments in speed and gradient until the respiratory exchange ratio is ≥ 0.95. Primary outcomes will be compared among groups and adjusted for any covariates (e.g., BMI, body fat percentage) as necessary.

Eligibility criteria: Inclusion Criteria:

* male
* age 25 - \<45 years
* Chinese, Indian or Malay based on self-identity for three generations (parents and grandparents)
* BMI ≥ 23 - \< 30 kg/m2 and/or waist circumference ≥ 90 cm
* physically inactive defined as \< 150 minutes moderate or \< 75 minutes vigorous leisure-time physical activity per week, or the equivalent combination of both

Exclusion Criteria:

* females
* personal history of cardio-metabolic diseases
* dieting (i.e. restricting food/energy intake)
* smokers
* consuming alcohol \> 3 times per week with \> 3 drinks per time
* using any medications which affect carbohydrate or lipid metabolism
* any lower body injuries
* fasting blood glucose \> 6.1 mmol/L

Primary outcomes:
measure: Cardiorespiratory fitness
timeFrame: 1 day (Single measurement)
measure: Resting fat oxidation
timeFrame: 1 day (Single measurement)
measure: Maximum fat oxidation (exercise)
timeFrame: 1 day (Single measurement)
Secondary outcomes:
Other outcomes:
Locations:
city: Singapore
country: Singapore
facility: Human Bioenergetics Laboratory, National Institute of Education, Nanyang Technological University
Study officials:
affiliation: Nanyang Technological University
name: Stephen F Burns, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Demashkieh M, Dalan R, Burns SF. Cardiorespiratory fitness and fat oxidation during exercise in Chinese, Indian, and Malay men with elevated body mass index. Appl Physiol Nutr Metab. 2022 Aug 1;47(8):888-892. doi: 10.1139/apnm-2022-0106. Epub 2022 Jun 9.