activities adrenaline adventure adventurers anecdotes athlete autobiography bio023000sel021000spo029000 biography biologicalsciences caldwell climbing collegesuccess determination endurance english exploration explorers fear generalinterests health hobbies inspiration inspirational limits memoir mental-strength motivation motivational mountain mountaineering mountaineers nutrition outdoor-life outdoor-sports personalmemoirs physical-challenges recreation risk rock-climbing rockclimbing self-help self-helpgeneral sports tommy triumph unitedstates