Ersha

All Gain, No Pain

You've tried before. You pushed through. And then you stopped. Not because you're lazy. Because it was awful. The struggle itself is the problem. One brutal workout teaches your brain that exercise is a threat. Eventually, you quit—not from weakness, from self-preservation. Ersha does it differently. Ersha uses your Apple Watch heart rate to keep you in Zone 2—where real cardio builds without the suffering. Blue light means you're perfect. Drift too high, we'll nudge you to ease up. That's it.