Time Restricted Eating Plus Exercise for Weight Management

Time restricted eating (TRE) is currently the most popular form of intermittent fasting which involves confining the eating window to 8-10 hours (h) and fasting for the remaining hours of the day. TRE is unique in that during the eating window, individuals are not required to count calories or monitor food intake in any way, resulting in high adherence. Accumulating evidence suggests that TRE produces a natural energy deficit of \~350-500 kcal/d. Physical activity in combination with a healthy diet pattern is recommended for older adults. While aerobic type exercise is the most commonly recommended, retention of lean mass via resistance training, especially in older adults, may be more effective at improving mobility, neurological and psychological function, executive and cognitive functioning, and processing speed. TRE combined with physical activity has not been examined in older adults or in people with overweight or obesity. This study holds the potential to 1) decrease body weight 2) improve lean mass 3) improve insulin sensitivity, and 4) improve attention, executive functioning, and processing speed in older adults. The aims of this study will examine the effect of TRE combined with either resistance training or aerobic training on body weight, body composition, metabolic disease risk, and cognition in adults over age 50. It is hypothesized that the TRE combined with resistance training group will see the most significant improvements in body composition, insulin sensitivity and cognition due to lean mass accretion.

Time restricted eating (TRE) is currently the most popular form of intermittent fasting which involves confining the eating window to 8-10 hours (h) and fasting for the remaining hours of the day. TRE is unique in that during the eating window, individuals are not required to count calories or monitor food intake in any way, resulting in high adherence. Accumulating evidence suggests that TRE produces a natural energy deficit of \~350-500 kcal/d. Physical activity in combination with a healthy diet pattern is recommended for older adults. While aerobic type exercise is the most commonly recommended, retention of lean mass via resistance training, especially in older adults, may be more effective at improving mobility, neurological and psychological function, executive and cognitive functioning, and processing speed. T TRE combined with physical activity has not been examined in older adults or in people with overweight or obesity. This study holds the potential to 1) decrease body weight 2) improve lean mass 3) improve insulin sensitivity, and 4) improve attention, executive functioning, and processing speed in older adults. This study will examine the effect of TRE combined with either resistance training or aerobic training on body weight, body composition, metabolic disease risk, and cognition in adults over age 50. It is hypothesized that the TRE combined with resistance training group will see the most significant improvements in body composition, insulin sensitivity and cognition due to lean mass accretion.

Eligibility Criteria:
Inclusion Criteria:

* Adults with obesity (BMI between 30-50kg/m2)
* pre-diabetes (fasting glucose: 100-125 mg/dl or HBA1c 5.7%-6.4% or OGTT ≥ 200 mg/dl)
* sedentary or lightly active (\<7,500 steps/day)
* between the ages of 50-80 years

Exclusion Criteria:

* diagnosed with T1DM or T2DM (fasting glucose: \>126 mg/dl, 2-h glucose OGTT ≥ 200 mg/dl,
* HbA1c: \>6.5%)
* Individuals with a history of eating disorders
* shift workers
* Individuals taking drugs to control body weight and glucose (including metformin)
* individuals who are not weight stable (weight gain or loss \> 4 kg) 3 months prior to the intervention
* mobility disorders or individuals unable to exercise for 40-60 minutes 3-4 days/week
* Individuals diagnosed with comorbidities impacting cognition, including major/mild neurocognitive disorder, cerebrovascular disease (e.g., stroke, aneurysm, arteriovenous malformation), traumatic brain injury, epilepsy, or major psychiatric disorder (e.g., schizophrenia, bipolar disorder, substance use disorder)
* Individuals who are unable to adequately report dietary intake or physical activity
* Smokers