Apple Watch data reveals US states where people get the most - and least - exercise (and number one ISN'T where you'd expect)

People in Massachusetts get the most exercise in the US, according to new Apple Watch data.

Only 54 percent of the US are hitting the recommended 2.5 hours of exercise a week, the study found.

Researchers from Brigham Women's Hospital used data from 92,793 US adults who consented to having their Apple Watch metrics collected.

Users' activity levels were tracked via arm motion, accelerometer, GPS and heart rate - all of which are detected by the watch.

Most participants (26.7 percent) were aged between 35 and 44, and 63 percent were male.

The CDC recommends 2.5 hours of aerobic exercise a week, which equates to just five 30-minute brisk walks.

People in Massachusetts may be the keenest exercisers, with 67 percent of study  participants from the region hitting that goal.

New York (66 percent) and Connecticut (64 percent) and California (62 percent) had the next highest percentages of people getting 150 minutes of weekly aerobic exercise.

Meanwhile, Mississippi had the lowest proportion of exercisers - 39 percent - followed by Louisiana, (41 percent), Oklahoma (41 percent) and West Virginia (42 percent).

A key limitation of the study is that the participants were adults who track their fitness data using an Apple Watch, meaning they are likely to be health-conscious.

Some 31 percent of participants were a healthy weight, while 35 percent were overweight and 32 percent were obese.

In the US, nearly one in three adults are overweight, and two in five are obese.

Alongside the 150 minutes aerobic exercise, the CDC also advises getting two additional days of muscle-strengthening activity. 

In other research, Massachusetts was also been ranked the most fitness-obsessed state.

The Apple study also found that 70 percent of participants aged 65-75 hit the CDC's recommendation of 2.5 hours of exercise a week, the highest proportion of any age group.

This was followed by 55-64 year olds with 68 percent. Those aged 25-34 had the lowest proportion, with just over half (52 percent) reaching the fitness goal.

The researchers also analyzed the percentage of workouts recorded at any given hour of the day in participants, and compared higher and lower cardio fitness groups.

Most participants in the higher cardio fitness groups worked out in the morning, between 7am and 8am.

In the lower cardio fitness group, most people started their workout between 5pm and 6pm.