Posted by: clint | 2012/10/16

Hi Nicci,
This is called an exercise headache which generally lasts for an hour to 4hrs. Several reasons exist why you could be experiencing these headaches. If you''re doing stressful exercise eg cardio, weight training, your heart starts pumping more blood, causing the vessels in the brain to dilate/expand which can cause a headache.
Other reasons, include not having enough glucose in the body. Example, if you''re training at a high intensity, and you did not supplement with a good preworkout supplement or have a meal within the 2hr period prior to the workout, chances are your blood-sugar levels are low, resulting in a headache.
Suggestion:
Adjust your training intensity i.e Start at slow/medium pace and increase slowly to help your heart adjust to the extra work. Our workouts should be paced appropriately.
Have a nutritious snack consisting of complex carbohydrates. eg. pasta which digests slower, raising the glucose levels slower.
Hope this helps.

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