Hi yannimac, do you check your heartrate when you exercise? I have been doing some indoor cycling again since Nov. I started with 15 min. and worked my way up to 30 min., but a week ago I raised my heartrate (I use a monitor) to 120 for a while and I was more dizzy for a few days. So after taking a few day off, I am back down to 25 min. and working only up to 110 bpm. It is very frustrating, but I feel better when I do something. Hope this helps and good luck with the neurofeedback.