The effect of training vs. spontaneous adaptation and natural development by age.
Red and blue circles represent performance before (Pre) and after (Post) training, while color-coded arrows indicate individual ST gains after training. The red line is the linear fit between age and ST before training and represents the spontaneous adaptation and natural development in children with HH. The blue line is the linear fit between age and STs after training. The amount of ST improvement obtained by training (delta Y, blue stippled line) is about 130 s (average over all patients) and could theoretically only be achieved after approximately 6 years of spontaneous adaptation (delta X). The green line represents the STs of the healthy children, showing only a small decrease with natural development. Arrows represent individual improvements of the patients before and after training.