When barefoot running guru Christopher McDougall takes in a neglected donkey, his aim is to get Sherman back to reasonable health.

But Sherman is ill-tempered, obstinate and uncooperative - and it's clear his poor treatment has made him deeply fearful of humans. Christopher knows that donkeys need a purpose - they are working, pack animals - and so when he learns of the sport of Burro Racing or running with donkeys, he sets out to give Sherman something worth living for.

With the aid of Christopher's menagerie on his farm in rural Pennsylvania, his wife Mika and their friends and neighbours including the local Amish population, Sherman begins to build trust in Christopher. To give him a purpose, they start to run together. But what Sherman gains in confidence and meaning is something we all need: a connection with nature, the outdoors, with movement. And as Christopher learns, the side benefits of exercise and animal contact are surprising, helping with mental and physical health in unexpected ways.