A joint Norwegian-Australian study has reported women with overweight/obesity issues who observed a dual regimen of time-restricted eating (TRE) combined with high-intensity interval training (HIIT) for 7 weeks ‘showed greater improvements in metabolic health’ than either intervention alone.
The study by scientists at the Norwegian University of Science and Technology and the Australian Catholic University in Melbourne, reported in Cell Metabolism, also noted these participants showed ‘high levels of adherence to TRE and HIIT alone and in combination’.
TRE involves restricting intake of calorie-containing foods to a specific time window – typically between 6-12 hours during the day – but does not limit either the types of food consumed or intake of calories during the eating window.
HIIT involves repeated short bursts of high-intensity exercise, interspersed with periods of rest or low-intensity activity.
For this study, researchers specifically examined the separate and combined effects of TRE (in a 10-hour window during the day) and HIIT (3 sessions of treadmill exercise per week) on 131 women of reproductive age with overweight/ obesity problems.
Participants in the combined TRE + HIIT group showed:
- greater reduction in levels of glycated haemoglobin (a measure of long-term glycaemic control) than either intervention alone;
- a two-fold greater decline in total and visceral fat mass (fat that surrounds abdominal organs, a risk factor for diabetes and other metabolic diseases) than TRE and HIIT in isolation.
Norwegian co-author Dr Trine Moholdt told medicalnewstoday.com: ‘Our findings of improved body composition, metabolic health and high adherence rates suggest women at high risk for cardiometabolic disorders can improve their health with a combined TRE + HIIT program – and that it is safe and feasible for this population.’
However Australian co-author Dr John Hawley warned the study only included females and ‘must be replicated in males’, as well as adding: ‘Participants in TRE reported eating less, so we don’t know if the positive effects of TRE were due to reduced energy intake or the timing of meals per se.’
Dr Moholdt summed up: ‘A two- year follow-up study will give us insight into how TRE and HIIT might be maintained after a familiarisation period provided through a study setting, and whether any health benefits initially induced by the interventions are maintained over the long term.’
