As a 10-mile-a-day runner, Dave McGillivray thought he could eat whatever he wanted without worrying about his heart. "I figured if the furnace was hot enough, it would burn everything," said McGillivray, who is 59.

But a diagnosis six months ago of coronary artery disease shocked McGillivray, a finisher of 130 marathons and several Ironman-distance triathlons. Suddenly he regretted including a chocolate-chip-cookie recipe in his memoir about endurance athletics.

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