The higher the height, the more response in the body.
However, this phenomenon is limited by the sleep quality that decreases with (too) high altitudes.
Finding the ideal height is therefore balancing between sufficient 'hypoxic stress' without losing too much in sleep quality.
Our experience with athletes indicates that 2500m is the most ideal height for most athletes. Furthermore, it is also known that this 'ideal height' can shift upwards as the athlete has more experience with height. Generally speaking, we advise against sleeping above 3500 meters. An exception to this are mountain climbers who wish to acclimatize for their next expedition. This is a very individual story. Hereby it is best to contact us for individual advice and guidance.