Hi welcome to HCM Dear your problem of lightheadedness and seeing spots in vision while exercising , is not uncommon . I can understand your concern . Headache, dizziness and lack of energy are the symptoms of post workout fatigue, when the diet is not proper. if intensity of your physical exercise has increased, then there must be inxrease in the diet also, failing which, these symptoms will persist. You should keep in mind that without inclusion of proper balanced diet containing all essential nutrints , your exercise lowers your energy level resulting the present smptoms by weakening the immune system . Before starting actual exercises ,warming up work out should be performed .Youcan also include Deep Breathing , Anulom Vilom , Bhramari & meditation to strengthen your heart and , in fact whole body , but increase gradually . Never over do . Avoid constipation , sleeplessness ,stress ,tea ,coffee , smoking ,alcohol water intake is very essential . Take lemon juice in a glass of water with a pinch of salt & pepper 3-4 times a for instant energy . Coconut water has essential nutriens and enlivens the soul instantly . Regular follow up with your doctor is necessary Hope this helps solve your query . Take care .All the best . Dont hesitate to come back if have further query .