When you exercise, or exert yourself physically, the muscles of the head, neck, and scalp need more blood to circulate. This causes the blood vessels to dilate, which can lead to a condition called exertional headaches. Headaches that most frequently occur due to exercise or over-exertion include jogger's headache and orgasmic headache (sex headache). While these may occur in isolation, they are most common in people who have an inherited susceptibility to migraine (one or both parents have migraines).
Closed beta is beta testing only available to a select few individuals or only company employees. How to be a beta tester. Many games (especially online games) in the final stages development have an open beta for several months that allows anyone interested in the game to play and report problems.
Early access. Early access, alphafunding, or paid-alpha is a funding model in the video game industry by which consumers can pay for a game in the early stages of development and obtain access to playable but unfinished versions of the game, while the developer is able to use those funds to continue work on the game.