Do Fitness Trackers Actually Make People More Active? About 1,800 Steps a Day at First. The Design Decides What Lasts

In 2016, a two-year trial gave half of 471 young adults in a weight-loss programme a wearable activity tracker. They lost less weight than the half without one: 3.5 kg against 5.9 kg [4].

That result sits awkwardly beside the headline evidence. A 2022 umbrella review in The Lancet Digital Health pooled 39 systematic reviews covering about 164,000 people, across every age group and both healthy and clinical populations, and concluded that activity trackers do increase activity by a clinically meaningful amount [1]. Both findings are true. The gap between them is what anyone buying a wearable programme, whether an employer, insurer or health plan, needs to understand: the effect shrinks over time, a tracker on its own does less than a tracker in a programme, and used the wrong way it can make results worse.

Do fitness trackers actually work?

Yes: on physical activity, the evidence is as consistent as it gets in behavioural health. The questions that matter to a buyer are how long the effect lasts and what it depends on.

Do the effects of fitness trackers last?

Partly. The gain is largest in the first months, about 1,850 extra steps a day after a mean of 13 weeks [2]. In the umbrella review’s longer-term analyses it was about 1,127 steps at four to six months and about 494 up to four years [1]. Game-based programmes show the same shape: in the STEP UP trial, the competition group’s lead over control fell from 920 to 569 steps a day once the game ended [6].

A programme that promises 1,800 extra steps is quoting the early effect. A realistic long-term expectation, on the pooled evidence, is closer to 500, and that is still worth having.

Do fitness trackers help you lose weight?

Modestly on average, and not on their own. Pooled studies show about 1 kg of weight loss [1]. In the IDEA trial, both groups improved their fitness and activity similarly, yet the group with wearables lost less weight [4]. The lead investigator’s interpretation was that the device may have drawn attention away from diet and the other behaviours that matter more for weight. A tracker is not a substitute for counselling.

Do incentives and games make trackers work better?

They can, for as long as they run.

TRIPPA: the incentive worked until it stopped. Employees from 13 organisations in Singapore were given a Fitbit alone, a Fitbit with charity incentives, a Fitbit with cash incentives, or nothing [5]. At six months, the tracker alone did not produce a significant increase in moderate-to-vigorous activity; cash incentives produced the largest gain, about 29 minutes a week. After the incentives ended, the gains disappeared, and at 12 months there was no improvement in weight, blood pressure or fitness in any group.

STEP UP: competition outlasted kindness. In a trial of 602 adults with overweight or obesity, three game designs, built around support, collaboration or competition, all increased daily steps over 24 weeks. Competition did best, at 920 steps a day more than the control group, and it was the only design still clearly above control 12 weeks after the game ended, at 569 steps [6].

The pattern across them: a tracker is a measurement tool, not an intervention. It works when it is part of a programme that changes what people do, and it can backfire when it replaces one.

How much are 1,800 extra steps a day worth?

Extra steps matter most for the people taking the fewest. In a meta-analysis of 15 cohorts and 47,471 adults, people in the lowest quarter averaged about 3,500 steps a day, and the three higher-activity groups, averaging about 5,800, 7,800 and 10,900, had a 40% to 53% lower risk of death [7]. The benefit levelled off at around 6,000 to 8,000 steps a day for older adults and 8,000 to 10,000 for younger adults.

This is observational evidence, and it does not mean any given 1,800 steps cuts mortality by a fixed amount. What it does show is where the gains are steepest: moving someone from 3,500 steps towards 5,500 is a far larger health change than moving someone from 11,000 to 13,000. We covered the evidence behind step targets in the 10,000 steps myth.

That has an uncomfortable implication for programme design. The people most likely to sign up for a tracker programme, and to keep wearing the device, are often the already active. In our review of abandonment data, 80% of people who chose a tracker were still using it at six months, against 46.5% of patients who were given one (wearable abandonment after six months). A programme can look successful while mostly measuring the people who needed it least.

What makes a wearable wellness programme work?

The evidence points to seven design choices:

1. Never deploy the tracker alone. Pair it with goals, coaching or counselling. Combined programmes produced effects about 50% larger [3], and in the IDEA trial the tracker without that focus did harm [4].
2. Personalise goals and prompts. Programmes with text messaging and personalisation features were more effective in the trial meta-analysis [2]. A fixed target ignores where each person starts.
3. Use competition, carefully. Of three game designs, competition produced the largest effect and was the only one that held after the game ended [6]. It also suits some people far better than others, so offer it rather than impose it.
4. Plan for the end of incentives. Cash moves behaviour while it is paid and can leave nothing behind [5]. Taper incentives, tie them to habits rather than single numbers, or budget for them as permanent.
5. Aim at the least active. The steepest health gains are at the low end of the step range [7]. Recruit, design and report for that group specifically.
6. Expect the fade, and design for it. Refresh goals, rotate challenges and re-engage at the points where activity typically drops, rather than reporting the first quarter’s numbers as the programme’s effect [1].
7. Measure against a comparison group. Volunteers differ from non-volunteers before they start, and seasons move step counts by about a tenth. We covered both in wellness programme KPIs and why step counts drop in winter.

What should you ask a wearable programme vendor?

• What is the effect at 6 and 12 months against a comparison group, not the change among participants since they joined?
• What share of enrolled people are still wearing the device at 3, 6 and 12 months?
• What were participants’ baseline step counts? How much of the effect comes from people starting below 5,000 a day?
• What does the programme do besides the device: goals, coaching, competition, incentives? Which of them does the result depend on?
• What happens when incentives stop?

Fitness trackers work. The evidence for that is as strong as it gets in behavioural health. What the evidence does not support is the idea that the device is the programme. The difference between 1,800 steps that fade to nothing and 500 that last for years is everything around the tracker: the goals, the people, the incentives and who it is designed for.