headache while working out

Yesterday I got a pulsing headache on the side of my head while pushing myself to finish a tough set , so I left . I went back today and while finishing a set of pull ups I got the same headache . What could be the problem ? The pain lessons when I just sit down and relax but I the headache lasts for An hour or so.

[gymdandee]

Exercise headaches are caused by exertion. But sometimes headaches after exercise can be a bleed in the brain.
If the headache is gone in a few hours after exercise  and you have no other  symptoms it's probably OK.But if you have really pounding headaches or headaches accompanied by nausea and vomiting or persistent headache for a few hrs after exercising then I suggest seeing a Neurologist.

Make sure you're well hydrated after exercising and do moderate exercising and stretching before and after a workout .You can also take Tylenol and ibuprofen.If the symptoms persist then see your doctor.