Where there was no expert opinion to the effect that the exertion contributed to the attack, unless and until some method is developed to ascertain with some degree of certainty that such an attack is not contributed to by exertion, we think that knowledge from *118 human experience, including medical caution against exertion in such cases and the admitted opinion of experts that exertion might contribute to such an attack, authorized the finding in this case, on the weight of reasonable probabilities; that the amount of exertion in this, case contributed to the cerebral hemorrhage which caused the deceased’s death. See Bussey v. Globe Indemnity Co., 81 Ga. App. 401, 405 (59 S. E. 2d, 34); Lumbermen’s Mutual Cas. Co. v. Bridges, 81 Ga. App. 395, 400 (58 S. E. 2d, 849); Fidelity & Cas. Co. v. Adams, 70 Ga. App. 297, 298 (28 S. E. 2d, 79); Travelers Ins. Co. v. Young, 77 Ga. App. 512 (48 S. E. 2d, 748); Williams v. Maryland Cas. Co., 67 Ga. App. 649 (21 S. E. 2d, 478).

The court did not err in affirming the award of the full board.

Judgment affirmed.