Optical HR reading 100 low during intensity?

[stevepetts372]

@Jack_Russell_Racing

Scosche RHYTHM for me on the upper arm works exceptionally well for indoor training. I have used the same unit for about 4 years with zero issues. The optical sensor in the Scosche IIRK is also much-adored by @dcrainmaker

Same for me - Rhythm 24 on the upper arm for many years with zero problems (apart from remembering to charge it)