[Effect of biguanide therapy on lactate metabolism during graded submaximal ergometric testing].

Diabetic patients were subjected to exercise testing before and after a short antidiabetic therapy with phenformin, buformin or metformin. Primarily, changes of lactate and of the acid base balance, were analyzed. After therapy with biguanides all 24 patients had increased lactate levels before and after physical strain. Phenformin showed the greatest influence on the lactate metabolism. Metformin the least.