# A Preliminary Investigation about the Influence of WIMU PROTM Location on Heart Rate Accuracy: A Comparative Study in Cycle Ergometer

## TL;DR

This study found that placing a WIMU PROTM device on the back or handlebars of a bicycle does not affect heart rate measurement accuracy when paired with a GARMINTM chest strap during cycling.

## Contribution

The study demonstrates that WIMU PROTM placement does not impact heart rate data accuracy when used with a GARMINTM chest strap.

## Key findings

- WIMU PROTM placement on the back or handlebars showed full agreement in heart rate measurements.
- Intra-class correlation values were excellent during all exercise phases (warm-up, time trial, cool-down).
- Bland–Altman plots confirmed minimal bias in heart rate measurements between device placements.

## Abstract

Technological development has boosted the use of multi-sensor devices to monitor athletes’ performance, but the location and connectivity between devices have been shown to affect data reliability. This preliminary study aimed to determine whether the placement of a multi-sensor device (WIMU PROTM) could affect the heart rate signal reception (GARMINTM chest strap) and, therefore, data accuracy. Thirty-two physical education students (20 men and 12 women) performed 20 min of exercise in a cycle ergometer based on the warm-up of the Function Threshold Power 20 test in laboratory conditions, carrying two WIMU PROTM devices (Back: inter-scapula; Bicycle: bicycle’s handlebar—20 cm from the chest) and two GARMINTM chest straps. A one-dimensional statistical parametric mapping test found full agreement between the two situations (inter-scapula vs. bicycle’s handlebar). Excellent intra-class correlation values were obtained during the warm-up (ICC = 0.99, [1.00–1.00], p < 0.001), the time trial test (ICC = 0.99, [1.00–1.00], p < 0.001) and the cool-down (ICC = 0.99, [1.00–1.00], p < 0.001). The Bland–Altman plots confirmed the total agreement with a bias value of 0.00 ± 0.1 bpm. The interscapular back placement of the WIMU PROTM device does not affect heart rate measurement accuracy with a GARMINTM chest strap during cycling exercise in laboratory conditions.