and he learned about an organization called achilles international. , achilles was as close to being invincible as any warrior could be. but even the greatest warriors can be hurt. achilles international encourages disabled athletes to compete in marathons and other public events. and they have a special chapter for members of our military. it's called the freedom team of wounded veterans. >> they meet the wounded vets, and then they give them the opportunity to participate in these events, and through these events, by doing these events, they can see their potential. they can see that they can be incorporated into society in a very positive way. >> it worked for staff sergeant de los santos. he was introduced to handcycling, and he signed up for a marathon -- 26.2 miles of fierce determination. ♪ >> that was my first marathon, and let me tell you, it was hard. and i made it. it was the best feeling ever, because it made me realize i did a marathon. if i can do this, i can do anything. >> in fact, since that first marathon, the sergeant has completed m