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A ring and personalised messages: a study of 56 adults

Study of 56 adults over a year, from UCLA Health: with a ring and personalised messages, sleep and activity improved more than in controls. A small group.

Updated October 20, 2026

A UCLA Health article from February 2022 describes a study by the university's researchers, published in Frontiers in Physiology in 2021. For a year, 56 adults wore a biometric ring that measures sleep and activity. For the first three months one group received, through an app, personalised messages written by a trained researcher; the other, the control group, received only general wellness education.

The limit of data alone

According to the article, many devices lead only to short-term adoption and temporary changes in motivation and habits: about one consumer in three stops wearing their device after six months.

Data on their own do not say what to do differently.

A couple in an elegant hotel bar in the evening: he smiles while she shows him the Digital Twin figure on her phone.

Ai-generated illustration

The missing step: planning the action

The article points to the step that is often missing: a moment where you plan what to do and commit to doing it.

In the study, the messages commented on each person's data: praising more steps, encouraging a slightly longer jog, or confirming that sleep was sufficient.

The result

Over the first three months, the group with messages improved significantly compared with the control group in time to fall asleep, daily steps, time spent jogging, VO₂max, body fat percentage and heart rate variability. Those who kept receiving messages for another nine months kept improving on these measures, except body fat; those who stopped largely kept their results. The authors conclude that a wearable combined with education, encouragement and personalised feedback produces more change than the device alone. It is a small study, of 56 people: it points to a direction, not a rule.

A habit is read in months, not in one meal.

The Digital Twin and this research

The Digital Twin lines up the data your devices write to your phone, such as steps, heart rate and sleep, and shows you how they change over time. It does not replace the people who look after you and it does not diagnose: this research describes groups of people, not you. These are data to read together with your doctor or the professional you work with.

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