Given the increasing prevalence of obesity, there is an urgent need to find better strategies to promote physical activity in the community. The present study will invite 70-year-olds with central (abdominal) obesity to participate in a 10-week aerobic exercise program. Participants will be randomly assigned to one of two equally large groups. The first group will complete the exercise program in instructor-led groups. The second group will complete the program at home with the help of an on-line video.

Central obesity means having a lot visceral fat, that is, fat located in the abdominal cavity. Visceral fat is a well-established risk factor for cardiovascular disease and all-cause mortality.

Participants will be recruited from the Healthy Ageing Initiative (HAI), an ongoing population-based study that invites all 70-year-olds in Umeå, Sweden, to a health examination. The exercise program will focus is on station-based aerobic exercises and resistance exercises, predominantly with participants' own body weight as resistance. The program is progressive, starting at a moderate pace so that participants learn to perform the exercises properly. The intensity will be aimed at 60-80% of maximal exhaustion, and each exercise bout will last 60 seconds with 20 seconds of rest between bouts. The program was developed by seniors in the bachelor's program in exercise physiology at Umeå University, Sweden.

Inclusion Criteria:

• Participated in the Healthy Ageing Initiative (a population-based intervention study in Umeå, Sweden)
• Visceral adipose tissue mass >1 kg (women) or >2 kg (men)

Exclusion Criteria:

• Physical disability that affects ability to perform the exercises
• Heart failure or severe degenerative condition (e.g. malignant cancer or multiple sclerosis)
• Myocardial infarction or stroke in the past year
• Heart condition that can worsen with aerobic exercise (e.g. angina)

The Data Analyst will also be masked.