PEMF once a week and moving well with age: what a Singapore study found

What the researchers did

This was a look back at records, not a trial set up in advance¹. A company in Singapore ran a weekly PEMF programme, and people joined mostly by word of mouth or after reading about it in the press. The researchers then looked at everyone over 35 who had finished all 12 weekly sessions and had complete records.

Each session was 10 minutes with a coil around the front of the thigh, the left leg one week and the right the next. The field was weak: the methods give 1 mT, though another part of the paper says 1.5 mT. About 85% did their 12 sessions in 12 weeks; the rest took up to 16 weeks because of holidays, travel or illness¹.

At the start and the end, everyone did three standard tests¹:

• Timed up and go: get up from a chair, walk 3 metres, turn, walk back and sit down.
• Five times sit to stand: stand up and sit down five times with arms crossed.
• Walking speed: walk 4 metres at a comfortable pace.

A smaller group stood on a body composition scale before their sessions: 42 people after 4 weeks and 33 after 8 weeks. 40 people also rated their pain before and after.

What they found

All three tests improved after 12 weeks¹:

• Timed up and go went from 11.25 to 9.31 seconds on average. In the oldest group, aged 76 to 91, it went from 15.35 to 13.14 seconds.
• Five times sit to stand went from 12.71 to 10.40 seconds.
• Walking speed went from 0.98 to 1.12 metres a second, and in the oldest group from 0.79 to 0.92.

At the start, the oldest were clearly slower than the youngest on every test. After 12 weeks that gap was no longer statistically clear¹.

On the scale, body weight didn't change. After 8 weeks, muscle mass was up 1.2% on average and rose in 24 of the 33 people measured. Total body fat was down about 3% after 4 weeks and about 4% after 8, and fat around the middle was down about 4% after 8 weeks¹.

Pain scores in the 40 people asked were lower at the end. The authors point out that pain medicine wasn't restricted during the programme¹.

What it didn't test

The authors call it a case study and say it needs a proper randomised trial¹. The limits are big:

• No comparison group and no pretend session. Everyone knew they were having PEMF, and expectation can't be ruled out.
• Only people who finished. Anyone who stopped early or had missing data was left out, which can make results look better.
• Other things weren't controlled. People could have other treatment and take pain medicine. The authors say other treatment made no difference to the scores, but it wasn't controlled.
• A mixed group. Most joined with an existing health condition or trouble moving, so it doesn't tell us much about healthy, active people.
• A body composition scale, in a smaller group. It was measured in 33 people at 8 weeks, not in everyone at 12.
• Conflicts of interest. The lead researcher holds a patent on the device and co-founded the company that ran the programme, and three authors worked for it. The company also provided the device and staff.

How this compares with a session at Sorted

The field in this study was weak, 10 minutes once a week, on one thigh at a time. A PEMF session at the studio is 25 minutes, with a loop or pad on the area you choose, and most people feel it as a rhythmic tapping. Our machine's settings aren't the same as this study's, so its results can't tell us what our sessions do.

It's still an interesting start for anyone thinking about how they'll move in 20 years. The authors compare their numbers with exercise studies in older people, but they didn't test exercise in this group, and the study can't tell us whether PEMF adds anything to staying active. We don't claim it does.