Overview
The purpose of this study is to investigate the suitability of intermittent exercise of long and short intervals at lower intensities than HIIE on energy expenditure during and post-exercise compared to MICE, as well as determine whether similar or greater effects can be achieved for glycemic control in recreationally active adults.
Description
The same procedure will be repeated for all trials: Participants will be asked to perform 4 trials in a randomized-crossover design [moderate-intensity continuous running (MICE: 60% V̇O2max), 5-minute interval running (5MIN; 50% and 70% V̇O2max), 2-minute interval running (2MIN; 50% and 70% V̇O2max), or a control with no exercise (CON)]. All trials will be separated by at least 4 days wash-out and less than 14 days between trials to ensure complete rest.
Sensors for measuring muscle oxygen (10 cm proximal to the mid-patella, and 2 cm lateral) will be placed on the rectus femoris muscle and 15 min resting metabolic rate was measured. A bilateral antecubital venous line for blood sampling will be inserted by a nurse. After baseline measurements, participants warm-up for 3 minutes with fixed walking intensity (i.e., 5 km/h) followed by 40 minutes running. Immediately after the running, participants return to a seated position for 30 minutes post-exercise measurements (EPOC). After the 30 minutes measurement, 5-minutes was given for participants to go to the bathroom and drink 100ml water, whereafter a standard 120-minutes oral glucose tolerance test (OGTT) is conducted (75g glucose dose with 50ml of water). The timer will be started at the first sip.
During the EPOC and resting metabolic rate (RMR) measurement participants will sit in a comfortable position and need to limit fidgeting, thus allowed only to watch TV or videos on their phone. During the OGTT, participants can do any calm activity such as watching TV, reading, working on the laptop, but no physical activity. Participants will be wheeled to the bathroom if needed.
Eligibility
Inclusion Criteria:
- Healthy recreationally active men
- BMI between 18.5-27 kg/m2
- Aged between 20 to 45 years
- Regular exercise (3 times per week and longer than 3 months) with cardio exercise longer than 30 minutes at least once a week
- Weight stable for more than 3 months (no change in weight +/- 3%)
- Non-shift workers and sleep at least 6.5-9 hours for the past 3 months
- Non-smoker
Exclusion Criteria:
- having any cardiovascular, metabolic or pulmonary disease (angina pectoris or uncontrolled arrhythmias)
- suffering from infectious contagious diseases,
- using medications that could affect metabolic responses (including anti-inflammatory medications)
- smoking
- heavy alcohol intake (more than 4 drinks on any day or more than 14 drinks a week).
- undergoing special diets (e.g., intermittent fasting and/or ketogenic diets)