Why you should exercise in short bursts and before bed, according to experts

Two friends walking together in an urban environment at night
Doing moderate to vigorous exercise, like brisk walking, climbing stairs, or jogging, can be beneficial in the evening. (Getty Images)

Can’t fit all your exercise into an hour-long gym session? Don’t sweat it. Scientists say that exercising in three-minute bursts is actually more important - and doing vigorous physical activity in the evening is even better.

According to researchers from the University of Sydney, people with obesity can benefit significantly from getting the majority of their daily exercise between 6pm and midnight.

The new study, published in the journal Diabetes Care, found that exercising in the evening is linked to the lowest risk of premature death and death from cardiovascular disease.

Doing physical activity later in the day was also associated with improved cardiometabolic regulation. This means that offsetting night-time insulin resistance - one of the key drivers of obesity-related complications, said Angelo Sabag, PhD, AEP, researcher and accredited exercise physiologist in the Charles Perkins Centre at the University of Sydney.

Sabag told Medical News Today that insulin resistance eventually leads to high blood glucose levels and type 2 diabetes. "Having high blood glucose levels can cause catastrophic damage to our cardiovascular system and lead to organ failure."

Insulin resistance is at its highest at night, and is particularly worse for people who cannot produce more to compensate. But exercising at night may offset some of this, Sabag said.

The fat man was running up the stairs. He lost weight.
Scientists found that, for people with obesity, working out in short bursts in the evening can result in significant health benefits. (Getty Images)

The researchers analysed the data of almost 30,000 people over the age of 40, from the UK Biobank, all of whom were classed as obese. Around 3,000 people analysed had type 2 diabetes.

The participants wore devices that monitored their activity levels in the morning, afternoon and evening over the span of eight years. The scientists found that people who did moderate to vigorous physical activity between 6pm and midnight saw the most health benefits.

The exercises that were tracked included both structured exercise and any type of continuous aerobic moderate to vigorous physical activity in bursts of three minutes or more.

Sabag said: "Physical activity, whether undertaken as structured leisure-time exercise, or incidental physical activity such as walking up the stairs, elicits profound health benefits.

"This finding seems to support the notion that doing multiple bouts of physical activity throughout the day may be more beneficial than accumulating all your physical activity in one block."

He added that the "repeated muscle contractions throughout the day may facilitate better blood glucose control", which results in "less risk of cardiovascular disease, organ failure, and other associated complications".

However, if your goal is weight loss, a previous study suggested working out between 7am and 9am is the best way to achieve this. Either way, experts agree that doing more physical activity is necessary as almost three in four people are not hitting the NHS-recommended target of 150 minutes of moderate exercise a week.

Best three-minute workouts to raise your heart rate

Gavin Cowper, exercise expert and owner of Exersci, outlines three workouts that can be done in three minutes to help you get active.

High-Intensity Interval Training (HIIT)

High-intensity interval training (HIIT) rose in popularity quite dramatically during the pandemic, and it has managed to stay relevant due to its significant benefits,” Cowper says. He recommends the following routine:

  • Star Jumps: Start with 30 seconds of star jumps to get your heart rate up and prepare yourself for the rest of the workout.

  • Bodyweight Squats: Follow your star jumps up with 30 seconds of bodyweight squats, ensuring proper form by keeping your back straight and lowering your hips until your thighs are parallel to the ground.

  • Mountain Climbers: Finish this mini HIIT workout with 30 seconds of mountain climbers, engaging your core and moving your legs in a running motion against the floor.

Repeat this circuit three times, with a 20-second break between each round.

Cardio

Cowper says: “This, unsurprisingly, is a cardio-focused workout that will get your blood pumping and your heart rate going in a short amount of time.”

  • Burpees: Perform as many burpees as you can in 30 seconds, combining a squat, jump, and plank into one fluid motion.

  • High Knees: Then, immediately transition into 30 seconds of high knees, driving your knees up towards your chest while standing in place.

  • Skipping: Finish with 30 seconds of skipping. This exercise is still championed by many elite athletes, especially boxers, and can easily be done from home.

Rest for 30 seconds after completing the circuit, then repeat for a total of three rounds.

Core

A core-focused workout can get your heart rate up.

  • Plank: Hold a plank position for 30 seconds, keeping your body in a straight line from head to heels.

  • Russian Twists: Sit on the floor, lean back slightly, and twist your torso to touch the ground on each side for 30 seconds.

  • Leg Raises: Lie on your back and lift your legs towards the ceiling, lowering them back down without touching the ground, for 30 seconds.

Repeat this sequence three times with a 20-second rest between rounds.

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