Blood donation is not problematic for athletes who do a normal amount of training. Nor will a blood donation get in the way of the ambitions of recreational athletes. It is advisable to wait a day or two after donating before engaging in very vigorous training or competition, though, because the body does need time to rest.
Of primary relevance for athletes is the reduction in the number of red blood cells (haemoglobin loss). This reduces the blood’s ability to transport oxygen, resulting in a temporary reduction in performance capacity. For this reason, athletes competing at a high level should not donate blood during the competition season.
Normally, recreational athletes barely notice the reduction in performance. And the life-saving effect for ill and injured people who urgently need blood is not to be forgotten.