It is one of the things he is using as inspiration, to push him onward as he nears the end of his cycling mission from Cape Reinga to Bluff.
The 25-year-old Auckland bartender passed through Dunedin yesterday on his ride to raise funds for his cousin Jack, who was diagnosed with the disease three years ago.
DMD is a recessive X-linked form of muscular dystrophy, affecting about one in 3600 boys, and results in muscle degeneration and eventual death.
Most do not survive past their teenage years.
Mr O'Malley said Jack was 5 when he was first diagnosed, and he recalled seeing the boy have his cramping legs massaged hard every night to loosen them.
It was ''totally heart-breaking'' listening to the boy crying himself to sleep, he said.
These days, Jack is confined to a wheelchair.
Mr O'Malley said he used Jack's daily battle as motivation to continue on his journey, despite the blisters and aching muscles from the long ride.
He had had several near misses with large trucks, including one near Auckland which ran over his bike.
''Initially, I didn't think I was going to make it.
''Cycling alone has been the hardest part. I'm a bartender and quite a sociable man, and I chat an awful lot.
''I've been by myself for 17 hours a day. But every time I stopped at a country pub, I chatted away nonstop. I'm sorry to any of the locals I've bumped into along the way.''
Mr O'Malley left Cape Reinga on September 16 and hopes to reach Bluff by next Monday, having cycled 2670km and raised almost $20,000 for people with DMD.
Mr O'Malley said he was realistic about his effort to find a cure for Jack.
''We hope that the children with Duchenne can benefit now, but the reality may be that future generations will be the ones who can walk into their adulthood and live long and full lives.
''I have already been run off the road by a lorry and scared myself half to death cycling through the night, but if I am able to bring hope or save a single life, then it will all be worth it.
''There's only about 270km left to go, so now I'm quite excited about finishing.''
To denote: www.justgiving.com/Luke-o-malley1
