As part of becoming empty nest, my wife and I made the decision to get our sorry butts back into shape. We have been very athletic up until about 8 year ago when we discovered how easy being lazy is. We have been working out with Trainers since about August and doing great, that is up until last night. I experienced what I can best describe as an explosive headache. Within a couple seconds I went from no headache to burning and pain in the back of my head and top of my neck. It stopped me in my tracks. I could not even get off the machine for a minute. I though it would go away but it took some time and the headache lingered into today. Needless to say this scared the you know what out of me and kind of freaked out my trainer. After googling this it appears that it can happen. Unfortunately the causes can range from just muscles and dehydration to possible life threatening things. I contacted my doctor and he responded not to worry, but because I have to be on a plane to China this weekend he is sending me in for a CAT scan Thursday. Have any you experienced this and if so what was the cause? 