Diet, Reducing
Conditions
Brief summary
Low-carbohydrate diets are often used as weight-loss strategies by obese individuals and athletes. This diet has effects on oxidizing fat and suppressing appetite. But short term evidences are still few. In combat sports such as taekwondo, athletes prefer rapid weight loss to achieve a desired weight category. The purpose of this study was to investigate the impact of the low carbohydrate diet combined with strict calorie restriction on body composition and exercise performance in taekwondo athletes.
Detailed description
This study used a randomized cross-over design. Each participant completed a low carbohydrate and a high carbohydrate trial in a random order, separated by a 30-day wash-out period. Each trial comprised of a 7-day weight loss period, followed by an 18-hr recovery period. The purpose of this study was to investigate the effect of 7-day caloric restriction with low- or high-carbohydrate diet, combined with an 18-hr recovery period, on body weight loss and taekwondo-specific performance.
Interventions
DIETARY_SUPPLEMENTcalorie restriction diet
The 7-day low-calorie diet contained 15.8 ± 0.4 kcal/kg/d in both trials, divided into three meals a day.
Sponsors
Chin Hsu
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Caregiver)
Eligibility
Sex/Gender
MALE
Age
20 Years to 24 Years
Healthy volunteers
Yes
Inclusion criteria
* Must have at least 6 years of Taekwondo training experience * Must have participated in domestic or international competitions
Exclusion criteria
* Smoking * Cardiovascular disease * Diabetes * Hypertension * Any medication in the past 3 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Body weight in kilograms assessed by air-displacement plethysmography (Bod Pod) | 1 min | The body weight (kg) of participants was determined before and after calorie restriction intervention to evaluate the degree of weight loss. |
| Body fat mass in kilograms assessed by air-displacement plethysmography (Bod Pod) | 1 min | The body fat mass (kg) of participants was determined before and after calorie restriction intervention to evaluate the degree of weight loss. |
| Lean body mass in kilograms assessed by air-displacement plethysmography (Bod Pod) | 1 min | The lean body fat mass (kg) of participants was determined before and after calorie restriction intervention to evaluate the degree of weight loss. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Taekwondo-specific reaction time in seconds assessed by Electromyography (EMG) signals | 1 min | The reaction time (sec) was measured before and after weight loss to assess the difference in exercise performance. The participants were asked to make the fist on the left hand as soon as they see a light signal, then start the taekwondo-specific movement. The reaction time was calculated as the time from the beginning of the light signal to the start of electromyography (EMG) signal of the left thenar muscles. The movement was performed 5 times. The average reaction time was used to arrive at one reported value. |
Countries
Taiwan
Outcome results
None listed