Days remaining before I leave warm and sunny Arizona for the Himalayas: 54. Simulated altitude at which I am sleeping with my hypoxic generator: 12,100 feet. Today's training: 60 minutes at level 18 on the elliptical machine. It took me four minutes to get my heart rate up to 153 beats per minute, which is 90% of my theoretical maximum. I sustained 153-161 beats per minute for the remaining 56 minutes. Then I spent another hour doing aerobic training on the step climber. The aerobic mode allows me to push my heart rate to at least 90% of my theoretical maximum and then recover slightly before pushing it back to 90%. It's all about increasing my VO2 max, anaerobic threshold, and lactic acid threshold. I doubt very much if there has ever been a climber gasping for breath on the summit ridge of Everest at 29,000 feet who thought to himself, "You know, I think I overdid it on the training."
This was me on the summit of Elbrus in Russia at 29 degrees below zero in gale-force winds, displaying that superior power of misery which distinguishes the human being and places him or her at a proud distance from the most melancholy chimpanzee. Elbrus in Europe was the third mountain after Kilimanjaro in Africa and Aconcagua in South America on my quest to reach the highest point on each continent, the fabled Seven Summits.