Simplify the following text for a Grade 10 native English-speaking person.
Original: He trained himself to accept these abstinences in order to endure the most appalling fatigues , hunger , thirst , and wounds , so that when scouting or traveling where there was no water , he might still be able to exist .
Simplified: He trained himself to accept these abstinences to help him overcome hunger , thirst , and exhaustion .