Timing of exercise matters for early birds, night owls

Timing workouts to align with a person's preference for mornings or evenings could slash the risk of heart problems and improve sleep, according to a study.

Assessing patients to determine if they are early birds or night owls could be beneficial, particularly among those with high blood pressure or other heart risks, experts said.

The study, published in the journal Open Heart, examined chronotypes, the body's natural, genetic inclination to sleep and wake at certain times.

People commonly fall into the category of either early bird or night owl.

Researchers in the UK and Pakistan assessed the chronotypes of 150 people aged between 40 and 60 using a questionnaire and 48-hour core body temperature data.

All patients had at least one heart risk factor, such as high blood pressure, obesity or a lack of exercise.

They were randomly assigned to groups for exercise that either matched their chronotype or did not, with 60 workouts each scheduled between 8am and 11am, or 6pm to 9pm.

Of the 134 people who completed the exercise sessions, 70 were early birds, 34 of whom had exercise times matched to their chronotype, while 64 were night owls, with 30 matched to their preference for evening.

A number of measures such as blood pressure and fasting glucose levels were taken before the trial and three days after.

The study found that risk factors for heart problems, aerobic fitness and sleep quality improved in both groups over the 12 weeks.

However, matching exercise to chronotype reduced blood pressure more, along with improving functions such as heart rate, aerobic capacity and sleep quality compared with those who were mismatched.

The benefits were particularly pronounced in sleep quality and blood pressure, according to the study.

The effects were also larger among morning people than among night owls.

While researchers acknowledge that further studies are needed, they said the findings support including chronotype assessment in exercise prescriptions for cardiometabolic prevention.

"Personalised, time-matched exercise interventions may become a practical strategy in clinical and public health settings, potentially leading to better outcomes and improved engagement," the authors said.