Workout buddy: when exercising with a friend helps and when it backfires

What the research actually shows

The Community Guide, where a US expert panel supported by the CDC weighs up the evidence, reviewed nine studies of social support for physical activity in everyday settings. That meant things like walking groups, buddy systems or agreements with someone else to reach a set amount of activity. All nine found that people became more active. Time spent being active rose by 44 percent at the median. How often people exercised rose by 20 percent. Aerobic fitness went up by just under 5 percent.

One detail from the same review is worth pausing on: in one of the studies, highly structured support and more informal support worked about equally well. That suggests you do not need an organised group. One person who knows you are coming goes a long way.

Source: Community Guide, social support interventions in community settings (nine studies published 1980 to 2000). Figures are rounded. The evidence is old, but the panel rated it as strong and the recommendation still stands.

An early classic: bring three friends

In 1999, two American researchers recruited 166 people into a weight-loss programme. Half came alone. Half came with three friends or family members. Among those who came alone and got the standard programme, 76 percent finished it. Among those who came with friends and also got social support training, 95 percent finished. The gap widened afterwards: 24 percent of the first group kept all of their weight loss six months later, against 66 percent of the second.

The study was about weight loss, not exercise as such. It still says something about what company does to your ability to stick with something over time.

A partner who starts with you beats a partner who has always trained

The most useful finding for anyone in midlife comes from the English Longitudinal Study of Ageing (ELSA). Researchers followed 3,722 married or cohabiting couples in which both partners were 50 or older. They looked at people who were physically inactive at the start and asked: what happened if the partner changed?

The answer was clear. If the partner became active, 67 percent of men also became more active, against 26 percent if the partner stayed inactive. For women the figures were 66 and 24 percent.

The interesting part is the comparison with people whose partner was already active. Living with someone who had always exercised helped too. But the odds were almost twice as high if the partner started at the same time. A partner who already runs 30 km a week is not a bad role model. One who takes their first walks alongside you is a better one.

ELSA is an observational study. It shows a link between a partner's change and your own, but it cannot tell who influenced whom, or whether something else, such as a new doctor's appointment, was behind both.

The Köhler effect: you last longer when someone needs you

Group psychology has a phenomenon named after the German psychologist who first described it. The weaker member of a team performs better than expected, especially when the team's result depends on whoever gives up first. Nobody wants to be the one who lets the team down.

Researchers at Michigan State University have tested it on exercise in several studies. In one, 58 young women rode a stationary bike at the same effort over six sessions. Those who exercised alone lasted just under 11 minutes on average. Those who exercised with a stronger partner, where the session ended when the first person quit, lasted almost 22 minutes. That is roughly twice as long. And the partner was only present on a screen.

In an earlier study using planks, people held on longer in every partner condition than alone. In that study, making the session depend directly on the weaker partner added nothing beyond simply exercising alongside someone.

The participants were young students in a lab. The partner was prerecorded. Nobody knows how big the effect is for a 45-year-old training with a neighbour in real life. The direction, though, holds up study after study.

When company makes things worse

This is where the research gets more interesting than the usual advice to find a workout buddy.

Encouragement from the stronger partner can cut sessions short

In a study of 115 people, those who exercised with an online partner held on 79 seconds longer on average than those who exercised alone. But when the stronger partner offered verbal encouragement, sessions were 31 seconds shorter on average than when the partner stayed silent. The researchers suggested that the encouragement may have been heard as aimed at someone other than the participant, for example as the partner encouraging themselves. The stronger partner then seemed to be struggling, which raised doubts about whether they really were stronger. The paper was titled "Silence is golden".

Support without presence did not raise attendance

In a study at the University of Pennsylvania, 790 students were randomly assigned to four set-ups for attending exercise classes. In two, participants could compare themselves with others. In one, they were a supportive team with no comparison. In the fourth, the control group, they were on their own. Attendance was 90 percent higher in the set-ups with comparison. The support team did no better than the control group and, in raw numbers, slightly worse.

That does not make support worthless. It means a group chat full of thumbs-up emojis is not the same as someone waiting at the gate at six in the morning. The participants had an average age of 25 and were rewarded for turning up. Whether comparison works as well for a 45-year-old with an injury history, or what it does to enjoyment over time, the study does not say.

Your buddy's pace is not your pace

This is the risk that rarely gets mentioned. A fitter friend pushes the pace up. If you are coming back after several years off, speed is the thing to increase last. If you cannot talk in full sentences, you are running faster than an easy session should be. The talk test, and why it beats your watch, is in the guide to zone 2. What a safe start looks like after 40 is in the guide to starting running after 40.

A new exercise companion for eight weeks

A Swiss research team ran an unusual trial. Instead of asking people how much support they felt they had, they randomly assigned 220 people either to find a new exercise companion and train with them regularly for eight weeks, or to carry on as normal. Both groups exercised more during the study. Towards the end, though, the control group tended to slip back. The level of support participants reported fell slightly in the control group and held steady in the companion group.

A follow-up analysis looked at which kind of support mattered. Emotional support, meaning someone who cared and believed in you, was linked to more exercise through greater confidence in your own ability. Practical support, meaning concrete help to make sessions happen, had no measurable effect on exercise in that study.

After 60, family counts for more than friends

A 2017 systematic review brought together 27 studies on social support and physical activity in healthy adults over 60. Support aimed specifically at exercise was linked to more physical activity, especially when it came from family. Support from friends showed no clear link. Most of the studies were cross-sectional, so they show association rather than cause. Still, it is a reminder that your best workout buddy may already be sitting at the kitchen table.

How to pick a workout buddy who lasts

Here is what the evidence points to, translated into an ordinary week.

• Book the time, not the ambition. "Tuesdays at 6:15 by the playground" holds up better than "we should train together more". It is the same principle as tying a habit to a fixed situation, which we cover in the guide to breaking a bad habit.
• Let the slower person set the pace. If you run at different speeds, the faster one can add a loop at the end. The session itself runs at the slower person's pace.
• Have a minimum version. If your buddy cancels, do ten minutes on your own. A missed session is data, not a failure, but missing two sessions because someone else was ill is a pattern that is easy to avoid.
• Choose someone in the same life stage. A friend with the same working hours and the same number of children cancels for the same reasons you do. That makes it easier to find a time that actually works.

If nobody shares your schedule, your commute can become the session. Run commuting on your own has the advantage that nobody else has to fit in, as described in the guide to run commuting. If time is the problem in general, there are more options in the guide for when you have no time to exercise.

If you want a shared goal with a date on it, some races let you start as a pair. In Hyrox the division is called Doubles: you run all eight kilometres together and split the work at the stations. How to train for it together is in the guide to Hyrox for beginners.

When to get medical help

Training together is not a medical intervention, but getting going again after a long break can bring on symptoms that need to be taken seriously. A buddy who can see you may also be the first to notice.

Frequently asked questions

Is it better to exercise with a friend than alone?

For most people, yes. In nine studies of social support for physical activity, people became more active in every one, with 44 percent more active time at the median. What seems to matter is that someone expects you at a set time, not that you talk about training. If you prefer to train alone, that is perfectly fine too. What counts is that the sessions happen.

Does it help to exercise with your partner?

Yes. It helps most if you start at the same time. In an English study of couples over 50, 67 percent of men and 66 percent of women became more active if their partner did too, against 26 and 24 percent if the partner stayed inactive. Having a partner who had always exercised helped as well, but less.

Should my workout buddy be fitter than me?

A little fitter, not a lot. In lab studies, the weaker partner lasted longer with a stronger one. In one study they lasted longest when the team depended on both. But a friend in much better shape pushes the pace up, and that is a common route to overload when you are making a comeback. Let the slower person set the pace.

What should I do if my workout buddy cancels?

Do a shorter version on your own at the same time. Ten minutes is enough to keep the habit going. Decide on the minimum version in advance, so it does not become a fresh decision when you are already disappointed.

Does a virtual workout buddy work?

Partly. In several studies, people lasted longer with a partner who was only on a screen than when they exercised alone. But encouragement from the stronger partner shortened sessions. A supportive team with no comparison did not raise attendance either. What worked was someone actually being there, not someone sending a thumbs-up.

Evidence base: the Community Guide review of social support interventions for physical activity in community settings (nine studies); Wing and Jeffery in the Journal of Consulting and Clinical Psychology 1999 (166 participants, PMID 10028217); Jackson, Steptoe and Wardle on partner behaviour in JAMA Internal Medicine 2015 (3,722 couples, ELSA, PMID 25599511); Feltz, Kerr and Irwin in the Journal of Sport & Exercise Psychology 2011 (PMID 21808077); Irwin and colleagues in Annals of Behavioral Medicine 2012 (58 participants, PMID 22576339); Irwin, Feltz and Kerr in the Journal of Medical Internet Research 2013 (115 participants, PMID 23732514); Zhang and colleagues in Preventive Medicine Reports 2016 (790 participants, PMID 27617191); Rackow, Scholz and Hornung 2014 and 2015 (PMID 24989147 and 25854295); Lindsay Smith and colleagues in the International Journal of Behavioral Nutrition and Physical Activity 2017 (27 studies, PMID 28449673); NHS guidance on depression.