Not for everyone, but for some people, yes. If you're used to slouching and leaning back into your seat, your postural muscles have atrophied and lost strength. Sitting in your NuChair in neutral posture gently engages your postural muscles, strengthening them as you sit. You may feel some tightness and/or fatigue during the first 5-10 days. Once those muscles strengthen you won't notice it anymore. In fact you'll probably notice that your posture is stronger while standing and doing things other than sitting. So give it some time, even if you have to switch back and forth between your NuChair and your old chair for a while. It will be worth the effort!