bill9 - Hi, I can concentrate with a cup of green tea or something else, but wish to learn about new things too.

mark47 - The last time I needed concentration was during the ride, and I used CBD capsules to feel better and be sure that I wouldn't have any problems in case of emergency. Thanks to this page https://pezcyclingnews.com/newswire/supplement-and-equipment-tips-for-beginner-cyclists/, I learned about this way of coping with stress and other situations, and I believe you can take CBD oil too because it has many beneficial effects.