Appeal from a decision and award of the Workmen's Compensation Board. Claimant is an officer and a principal stockholder of the employer corporation which maintains a 67-car parking lot in downtown Manhattan. Claimant operates the lot himself with one helper, and the proof is that during the morning hours he engages in considerable physical activity in moving cars to get them off the street, creating "aisles" for cars, and other similar operations. In the course of this activity on February 10, 1958 claimant testified that while he was trying to maneuver an old-type car, the steering wheel of which was hard to turn, into parking position, he felt a pain in his chest and shoulders. After lunch he felt acute pains and this condition was diagnosed as an anterolateral infarction. He was hospitalized from February 12 to March 15. Claimant also testified that a week before this incident (February 3) he was shoveling snow in the parking lot and felt drawing pains in his shoulders. A cardiac specialist testified to the opinion that the physical effort described on the morning of February 10, including the difficulty in moving the old car, "would have been sufficient to produce the myocardial infarction in a man of that type" and he testified also to an opinion of causation based on a hypothesis which included the snow-shoveling effort of the week before. The award was sufficiently grounded in the medical opinion in this record. Award unanimously affirmed, with costs to the Workmen's Compensation Board.