Cramps when you exert yourself may be caused by calcium deficiency, lactic acid buildup, chronic strain injury, etc.
1. Calcium deficiency: Usually, back cramps may be caused by calcium deficiency, and calcium deficiency may lead to the phenomenon of back cramps upon exertion.
2. Lactic acid buildup: After strenuous back exercise, a large amount of lactic acid may build up in the lower back, resulting in muscle spasms, which may lead to the phenomenon of back cramps upon exertion.
3. Chronic strain injury: Frequent activities or weight bearing on the lower back may cause chronic strain injury, and gradually develop aseptic inflammation, which may lead to poor blood circulation in the lower back and the phenomenon of cramps when exerting oneself.
There are many other causes of lumbar cramps, it is recommended to consult a doctor to clarify the cause of the problem and then carry out the relevant treatment.