After crossing 65, brisk walking and yoga can be beneficial for overall health, but there's something more specific that can help this group of people with fat cutting and muscle mass preservation.

According to new research published in the Maturitas journal in December 2025, the answer is high-intensity interval training, aka HIIT workouts.

The lead researcher, Dr. Grace Rose, and her colleagues examined 123 healthy women and men aged 65 to 85 for six months. All participants were randomly divided into 3 groups and asked to perform three different 45-minute training sessions per week.

While performing these exercises, participants were monitored, and their heartbeats were measured. The three forms of exercise were:

• Low-intensity exercises: In this, participants followed exercises such as stretching and balanced classes for 45-minutes. While performing this, the peak heart rate of participants reached 45% to 55%
• Treadmill-based moderate-level exercise: During a 30-minute continuous treadmill workout, heart-rate reached to 60% to 70%.
• HIIT: When participants performed different movements in 4-minute intervals, their heart rate reached 85% to 95% of its maximum. A 3-minute recovery time between the internal sets was also provided, along with a 5-minute ending cooldown. 

During the research, the participants were asked not to change their diet and continue taking their medicines (if any). After 3 and 6 months, their body compositions were measured through dual-energy X-ray absorptiometry (DEXA) scans.

Outcome of the Research

It was found that the group following the HIIT method reduced the maximum body fat percentage. They also retained more muscle than the other two groups, although the HIIT and Treadmill-based moderate-level group had lost almost the same amount of fat mass. 

The observers concluded that thet “appropriate and feasible, higher-intensity exercise training may be considered to support improvements in health-related body composition in older adults.”

Bottomline 

According to exercise physiologist Jason Machowsky, HIIT can benefit aged people, but it's not the only way to achieve fitness. Both moderate and HIIT workouts help lose fat, but strength training helps preserve muscle mass.

Machowsky highlighted that HIIT can stress joints and also increase the risk of cardiac events, particularly in those who are suffering from diabetes. So, one must consult a doctor or any certified professional before starting it.

So, do you also practise HIIT workouts?

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Written by

Supradeep Dutta

Edited by

Souvik Roy