Can a Pacing App Prevent Long COVID Crashes? Trial Results

A six-month randomized controlled trial tested whether a digital pacing platform combined with a wearable activity tracker could reduce post-exertional malaise, or PEM, in adults with long COVID.

In this study, 250 participants were randomized to either receive the “Pace Me” app plus a Fitbit with real-time activity alerts or an app-only control version. The intervention sent notifications when participants reached 50, 75, and 100 percent of their personalized activity limit.

The primary outcome was PEM severity measured by the DePaul Symptom Questionnaire. After six months, there was no meaningful difference between the intervention and control groups. Both groups showed some improvement over time, suggesting gradual recovery rather than a specific benefit from the app.

Energy management and pacing are widely recommended for conditions that involve PEM, including long COVID and some autoimmune diseases. This well-designed trial found that adding real-time digital alerts did not reduce PEM compared to usual care.

For patients and clinicians, this highlights an important point. Digital tools may feel supportive and safe, but they are not guaranteed to reduce symptom crashes. More research is needed to determine whether similar approaches could help in conditions where recovery is less common, such as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or autoimmune diseases associated with persistent fatigue.

Citation

Sanal-Hayes, N.E., Hayes, L.D., Mair, J.L. et al. A digital platform with activity tracking for energy management support in long COVID: a randomised controlled trial. Nat Commun 17, 945 (2026). https://doi.org/10.1038/s41467-025-64831-y