Inaccurate heart rate during strength training

General
1

Hey everyone,
just wondering if anyone else has experienced similar issues – or found a workaround:

I’ve been using WHOOP since March 2024 and love the concept overall. The form factor is great, and I really want this to be my go-to tool for training, recovery, and health tracking.

But I’ve had persistent and severe issues with HR accuracy during strength training – and unfortunately, even after upgrading to the WHOOP 5.0 MG and receiving a replacement device via support, nothing has improved.

Here’s what happens:
• During heavy strength training (e.g. squats, deadlifts, leg press), my heart rate spikes to 150–160 bpm (confirmed with Apple Watch & chest strap).
• WHOOP, however, shows around 70–80 bpm during the set.
• Only once my HR drops back below ~120–130 bpm (usually during rest) does WHOOP “catch up” – meaning the actual intense effort is completely missed.

This happens consistently, regardless of:
• Tracking method (auto-detect, manual activity, Strength Training, or Strength Trainer)
• Strap position (wrist left/right, forearm, bicep band – all tested with tight/loose fits)
• Sensor care and placement (clean sensor, >2 inches above wrist bone, logo inward)
• Type of movement – it even happens during leg exercises where my arms barely move.

Outside of the gym, especially during cardio, the HR readings are perfectly fine.

I’ve been in touch with WHOOP support , followed all placement recommendations, sent photos, received a replacement unit – but the issue remains exactly the same.

I’m 185 cm, 88 kg, ~15% body fat – nothing extreme anatomically. No tattoos, clean skin, normal wrist size.

At this point, I’m wondering:
Is WHOOP simply not capable of tracking short HR spikes typical in strength training?

Would love to hear if anyone has found a solution – or if others are dealing with the same thing.

Thanks in advance,
Felix

2

I’m having a similar issue. My heart rate with my 5.0 was reading around 103-108 for my heart rate while my Apple Watch was reporting around 130-170 BPM… Seems like we’re going to need a firmware update to address this. I was definitely above 108… I am an athlete and can attest that the heart rate monitoring has been inaccurate during my workouts… hopefully Whoop can get this issue corrected in a timely manner if enough members are having this issue? The issue has been during open exercise recordings… my runs seem like they have been recording my HR correctly. I’ll need to pay attention to this during some of my biking sessions. My daytime heart rate during rest seems to be fine and inline with my other tracking devices.

1 Like
3

I also posted on Reddit and got tons of replies and messages. So we’re definitely not alone with this issue. I am also in contact with support AGAIN but seems like they can’t help with it. They try to blame it on how I am wearing the band but I am wearing it exactly like recommended, tried it on both wrists, inside and outside, on the bicep, even on my ankle. But the readings are the same each time. I just hope more people will write support with the exact same problem so they finally realize they have to change something.

4

I just got the whoop 5.0. I always used a Garmin Venu 3 which was within 1 beat of the heart rate monitor of the exercise machine. My whoop is constantly 20-40 beats lower during strength training. It clean, almost new and fitted properly.

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5

Yeah that’s super frustrating.

I have also posted on Reddit and talked to friends and got more than 20 replies from people having the exact same issues. If you dig a little there are also YT videos showing the exact same thing.

I just hope enough people write the support for them to change something because I still think it might be a software issue and not an actual hardware issue.

I am also in contact with support. They’re answering quickly and seem to be really interested in solving this issues. However no solution yet.

6

I can only recommend a bicep strap, which gives much better HR readings. Works with strength training, although it’s not at the wrist

1 Like
7

Thanks for the tip
But as I’ve already written in the post, a bicep band unfortunately doesn’t change the bad readings for me

8

Ah, sorry I missed that. For me it works great, compared to a Polar H10 chest strap delivers very accurate results during strength training