Intermittent fasting, a combination of high-intensity exercise can burn more fat

64 obese women were assigned to one of three groups: time-restricted eating (diet only), high-intensity functional training (exercise only), or time-restricted eating plus high-intensity functional training (diet + exercise ).

Participants only ate between 8:00 a.m. and 4:00 p.m., and those in the functional training groups worked out three days a week with an instructor.

After 12 weeks, all three groups had achieved significant weight loss and improvements in body composition. Favorable changes in lipid and glucose levels were also found.

Participants in the diet + exercise group achieved more remarkable changes in body composition and cardiometabolic parameters compared to the other two groups.

The authors said that combining time-restricted eating with high-intensity functional training is a promising strategy for improving body composition and cardiometabolic health.

However, they note that this is a small study and that more research is needed.

Registered dietitian Emma Shafqat, who was not involved in the research, says she is not surprised by the results of this study, although time-restricted eating does not appear to restrict the total calorie intake that is necessary for the weight loss

She said that studies have found that people often spontaneously reduce their energy intake when following an intermittent fasting plan, resulting in mild body weight loss (1%–4%) over periods of time lasting from 1 week to 3 months.

Similarly, celebrity personal trainer Michael Baah says that the combination of time-limited eating and high-intensity exercise tend to work well together.

When we limit the amount of time we eat and do intense workouts, our bodies improve their energy use and sugar processing, making them more efficient at staying healthy, he explains.

Vigorous exercise has added benefits when it comes to fat loss. Time-restricted eating helps us burn fat, and vigorous exercise helps us build muscle, Baah surmises.

This is good news for anyone looking to maintain their long-term weight loss, as lean muscle mass increases your body’s metabolic rate, which means you burn more calories.

In addition to leading to weight loss, the combination of time-restricted eating and high-intensity exercise can also lead to improvements in cardiometabolic health.

Cardiometabolic disease describes a series of conditions that begin with insulin resistance, progressing to metabolic syndrome, prediabetes, and eventually more serious conditions such as cardiovascular disease and type 2 diabetes, Shafqat explains.

She notes that time-restricted eating improves cardiometabolic health in many ways, for example by improving glucose tolerance, lowering blood pressure, and improving intestinal function.

However, time-restricted eating will not be the right weight loss tool for everyone.

The only way to lose fat is to be in a caloric deficit. For some people, time-limited eating is simply a tool to help them achieve that goal, Baah says. If they restrict their time to eat, that [often] it reduces total calories for the day, which puts them in a calorie deficit.

While this works for some, it may not fit your lifestyle or feel too restrictive. Eating under time restrictions isn’t the only way to lose fat. However, if you’re planning to follow a time-restricted eating plan, Shafqat says it’s key to make sure you’re feeling well-fed and satiated.

I recommend starting the day with a breakfast that’s high in fiber, protein and some fruit, for example whole-grain yogurt with seeds and fruit or porridge with added seeds and fruit, she says. I also recommend eating a good, balanced meal before 4pm that includes high-fiber carbohydrates, protein, and lots of vegetables to help stave off hunger before bed.

Shafqat says planning is key when it comes to eating under time constraints.

In this study, there seems to be an 8-hour schedule that participants can eat, so if you stick to that schedule. I recommend planning your meals and snacks and preparing your food in advance.

Even if you plan to lose weight, it’s a good idea to factor exercise into your schedule. If high-intensity exercise seems intimidating, don’t worry, Baah says.

Start with simple exercises and focus on using good form, she advises.

Ideally, you should aim for a combination of strength training and cardio. Some exercises Baah recommends include jumping jacks or lunges, incline rows, weighted sit-ups, and dumbbell reverse lunges.

The term high-intensity may conjure up images of grueling workouts, but Baah says it’s important to give your body time to rest and recover. Take a rest period of about 60 seconds between each set and plan rest days into your schedule.

The key to progress, according to Baah, is to make sure you lift heavier weights over time.

The combination of time-restricted eating and high-intensity exercise appears to contribute to fat loss and improve other health markers related to cardiometabolic health.

However, if your goal is to lose weight, the calorie deficit is the most important factor, and if you find time-restricted eating too restrictive, you should consider something else.