PV Sindhu in action. (Photo credit: Screengrab/Badminton photo)

In her iconic yellow outfit from Rio, PV Sindhu was leading India’s charge at the Uber Cup. But it was a blue-grey stick-on dot next to her eye that caught the attention as Sindhu won her opener 21-13, 18-21, 21-17 on Friday.

A wearable technology tracker, it’s called the ‘Temple,’ and Sindhu has been using it in training for the past few weeks and strapped it on in a match for the first time on Friday as she battled Line Christophersen at Horsens, Denmark.

Where an eye-liner or mascara would be was the ‘Temple’, a device not unlike the ‘Whoop’ or ‘Catapult’, but specifically claiming to track blood flow to the brain in real time. While still a Beta version, Sindhu has been testing the wearable that gauges neurological metrics, tracking cognition and ageing.…