Claude vs ChatGPT: Heart rate tracking without a chest strap for gym workouts. Join the debate.: Apple Watch SE

For a casual gym-goer who wants simple, comfortable HR tracking, the Fitbit Charge 6 is the sweet spot — accurate optical wrist HR, works across cardio machines and free weights, and doesn't demand the commitment of a full smartwatch. It sits around £130–£150 and pairs with most gym equipment via Bluetooth. If budget stretches a little further, the Apple Watch SE (2nd gen) gives better overall accuracy and a bigger ecosystem, but it's a bigger device at a bigger price. For casual use, the Fitbit is the call — it does the job without overcomplicating it.

Fair challenge. Battery life is a real differentiator here — the Fitbit Charge 6 runs around 7 days on a charge with continuous HR monitoring active, whereas the Apple Watch SE 2nd gen drops to roughly 18 hours in standard use, less with workout tracking running continuously. For a casual gym-goer, that gap matters practically: the Fitbit survives a week without thinking about it, the Apple Watch needs nightly charging without fail. If someone forgets to charge or just wants low-maintenance tracking, the Fitbit wins this comparison clearly. The Apple Watch SE is only the better call if they're already in the Apple ecosystem and want the broader smartwatch functionality beyond HR.

Optical HR accuracy does dip during high-intensity intervals for both devices — wrist movement creates noise. Independent testing puts the Apple Watch SE slightly ahead on accuracy during HIIT specifically, thanks to better sensor algorithms. But this person is a casual gym-goer, not an athlete optimising training zones. For steady-state cardio, weight training, and moderate effort sessions — which is what casual gym use looks like — the Fitbit Charge 6 is accurate enough to be genuinely useful. The accuracy gap only meaningfully matters at high intensity, and even then it's marginal for someone tracking general effort rather than precise zones. Final recommendation: Fitbit Charge 6. Better battery, lighter on the wrist, no chest strap, accurate enough for casual gym use. That's the right fit.