None listed
Conditions
Brief summary
Intermittent fasting diets have been shown to reduce body weight, fat mass, lower skeletal muscle insulin resistance and improve overall metabolic health. However, the specific mechanisms are far from being fully understood and the impact of intermittent fasting on lean body mass remains unknown. The present study assesses the effect of intermittent fasting regimens and continuous energy restriction on skeletal muscle mass and muscle protein synthesis rates in vivo in humans. We hypothesize that 1.) alternate day fasting and continuous energy restriction will reduce rates of muscle protein synthesis compared with a control diet and 2) time restricted eating will not lower muscle protein synthesis when compared with a control diet.
Interventions
The study design consists of a randomized, parallel-group intervention study in 40 overweight, middle-aged males. The study will involve a 3-day lead-in control diet for all intervention groups, after which subjects will be randomized to 10 consecutive days of either:
1. Alternate day fasting (ADF: 25 Energy percentage (En%) food ingestion on day 1, 3, 5, 7 and 100En% food ingestion on day 2, 4, 6, 8 and 10)
2. Continuous energy restriction (CER: daily intake of 62.5 En% of total energy intake)
The study design consists of a randomized, parallel-group intervention study in 40 overweight, middle-aged males. The study will involve a 3-day lead-in control diet for all intervention groups, after which subjects will be randomized to 10 consecutive days of either: 1. Alternate day fasting (ADF: 25 Energy percentage (En%) food ingestion on day 1, 3, 5, 7 and 100En% food ingestion on day 2, 4, 6, 8 and 10) 2. Continuous energy restriction (CER: daily intake of 62.5 En% of total energy intake) 3. Time restricted eating (TRE: daily intake of 100 En% of total energy intake in an 8 h time window) 4. An energy balanced control diet (CON: daily intake of 100 En% of total energy intake in a 12 h time window, according to current Australian Healthy Eating guidelines comprising a macronutrient intake of 50% En, CHO, 30% En fat and 20% En protein.). A labelled water protocol will be used to determine changes in integrated muscle protein synthesis rates. Prior to and after the diet intervention, a test day will be performed to assess muscle metabolism, body composition, and glycemic control. All food will be provided to the participants and they will visit the university twice throughout the 10-day intervention to pick-up their meals. A registered dietitian will provide a personal diet to every participant based upon individualized energy requirements. Adherence to the diet will be conducted through a food log and continuous glucose monitoring for timing of meals.
Sponsors
Australian Catholic University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
Male
Age
35 Years to 55 Years
Healthy volunteers
No
Inclusion criteria
- Male - Age: 35-55 years - BMI: 25-35 kg/m2
Exclusion criteria
1) Current diagnosis of Type 2 Diabetes (HbA1C >6.5% or 48 mmol/mol) 2) Unable to attend the laboratory for visits and adhere to the 3-day lead-in diet and 10-day intervention diet 3) Currently meeting physical activity guidelines (i.e. doing more than 150 min of physical activity per week or >10,000 steps per day) 4) Major or chronic illness that impairs mobility or eating/digestion; 5) Previous bariatric surgery; 6) Shift workers; 7) Smoker (cigarette, e-cigarette or marijuana); 8) Individuals with strict dietary intake regimes (i.e. vegan, avoidance of principal study foods); 9) Individuals who are currently restricting their dietary intake (i.e. actively trying to diet and lose weight) or participating in regular fasting (defined as fasting >16 h/day or having completed twelve 24-h fasts within the past year); 10) Participating in shift work (i.e. >3 h between 22:00 h and 05:00 h for 1 day per week (>50 days per year)) 11) Not weight stable (>5 kg body weight change over last 3 months); 12) Individuals who do not consume breakfast on at least 5 of 7 days per week (i.e. not eating regular meals); 13) On prescribed medications required to be taken with food in the early morning or late evening or taking other prescribed medications for <3 months. 14) On prescribed anti coagulation medications (interfering with muscle biopsy procedures)
Outcome results
None listed