I've designed a lot of small apartments, and the best desk-treadmill combos are the ones that don't take over. Try a minimalist desk with a low-profile treadmill to keep the space feeling open. Noise matters too. I've heard from renters that softer materials underfoot help keep the sound down for neighbors. Honestly, just figure out how much room you need to walk comfortably, then pick pieces that fit your space instead of dominating it.
For small apartments, the best standing desk treadmill is one that folds up and stays quiet. The one we use in our office doesn't interrupt video calls, which is a lifesaver in a shared space. If you're tight on room, make sure you can easily store it and check how loud it actually is before buying. This saves a lot of trouble later.
In small apartments, a standing desk treadmill works best when it integrates seamlessly into your lifestyle rather than dominating the space. I suggest choosing a foldable base you can slide under the couch and pairing it with a compact desk setup, so movement feels natural and not like an extra chore. Even walking slowly--say, 1 to 2 km/h--can help maintain focus and energy levels throughout the day without overwhelming your body or your floorboards.