Those who hit the gym after work may want to adjust their schedule, research suggests.
An American study of 5,285 middle-aged adults found that exercising between 7 a.m. and 9 a.m. was the best time to lose weight.
Participants in this category had a lower body mass index (BMI) and a smaller waist circumference than people who exercised in the afternoon or evening. This despite the fact that they spent more time sitting than the others.
Scientists say morning exercise may be best because it’s easier to stick to the schedule and people are less likely to be distracted by phone calls, emails or meetings.
An American study among 5,285 people found that exercising between 7 a.m. and 9 a.m. was best for losing weight (Stock Image)
Dr. Rebecca Krukowski, a clinical psychologist at the University of Virginia, said: ‘This is exciting new research that is consistent with a general tip for achieving exercise goals.
“That means scheduling exercises in the morning before emails, phone calls, or meetings can distract you.”
However, she admitted that the results could be attributed to other factors, such as having a more predictable schedule or not having any caregiving responsibilities.
She added: ‘Predictable schedules may have other beneficial effects on weight that were not measured in this study, such as sleep duration and quality or stress levels.
“Additionally, the ‘morning larks’ who consistently get up early enough for morning exercise may be biologically different from their ‘night owls’ counterparts.”
Research shows that people who get up earlier have a circadian rhythm – or “body clocks” – that run earlier, which could improve sleep quality and ensure a consistent schedule, all of which can lead to weight loss.
Scientists found that people who were early risers were 10 to 13 years older than those in the other two groups.
Most of them also had a university degree and said they had never smoked or consumed alcohol. They also had healthier diets and ate less than those in the other two groups.
For the study, published today in the journal Obesityscientists looked at data from the official National Health and Nutrition Examination Survey (NHANES) – which assesses the health of approximately 5,000 adults and children in the US each year.
They used data from 2003 to 2006, when participants wore fitness trackers – or accelerometers – on their hips to track exercise for seven consecutive days.
Although NHANES still uses fitness trackers, they are now worn on the wrist, making comparisons with more recent years less reliable.
The study used data from the trackers to divide participants into three groups: in the morning, or from 7 a.m. to 9 a.m., in the afternoon, between 11 a.m. and 1 p.m., or in the evening, from 5 p.m. to 8 p.m., athletes.
Scientists then collected data on BMI and waist circumference in each group to find out which group was least likely to be obese.
Of the participants, 642 were in the morning group, while 2,400 trained in the afternoon and 2,187 in the evening.
BMI was lowest in the morning group at 25.9 kg/m2, putting them just above the healthy range of 18.5 to 24.9 kg/m2.
The results were similar between the afternoon and evening groups, which had BMIs of 27.6 and 27.2 kg/m2 respectively, putting them in the overweight category.
Waist circumference was also lowest in the morning group: 36 inches (91.5 centimeters).
In the evening group it was 37.4 inches (95 cm) and in the afternoon group it was 37.7 inches (95.8 cm).
Dr. Tongyu Ma, an exercise physiologist at Franklin Pierce University in New Hampshire, added: ‘Our findings suggest that the daily pattern of moderate to vigorous physical activity could be another important dimension to describe the complexity of human movement.’
Researchers are divided on the best time of day to exercise to boost weight loss, but several studies suggest morning is best.
A 12-week study of 100 adults from Skidmore CollegePublished last year, New York suggested that women interested in losing fat should exercise in the morning.
Another newspaper from the Swedish Karolinska Institute published earlier this year also suggested that exercising in the morning was best for weight loss, after finding that mice had a higher fat metabolism when they exercised early in the day.