How do you grasp oars if you don't have thumbs? How do you pull a boat through the water if you don't have a bicep? And how do you win a gold medal in cross country skiing if you have a broken arm?

The thing about Oksana Masters — who did all of these things — is this: She doesn't want to hear "You can't" from doctors, trainers or anyone. She just tells herself, "I can." And then she does.

Her memoir, "The Hard Parts," co-written with freelance writer Cassidy Randall, tells an incredible story.

Masters was born in Ukraine three years after the meltdown at Chernobyl. She had a multitude of physical anomalies — no thumbs, to start. Five webbed fingers. No bicep on one arm. Only one kidney, only part of a stomach. Her left leg was 6 inches shorter than her right leg and she had no tibias — that weight-bearing shinbone —in either leg. She had 12 toes.

This, apparently, is what can happen when you are born in the irradiated countryside around Chernobyl. She was also born, though, with an extraordinary amount of fortitude. Grit, stubbornness, determination — call it what you will, when you read her memoir, you will realize that the subtitle ("A Memoir of Courage and Triumph") doesn't begin to cover it.

The first section of the book is short, fewer than 50 pages, but it echoes throughout the rest of the narrative. It tells of her seven years in an orphanage in Ukraine, which was worse than you might think. Details are doled out in brief sections set off by the word "blink" — as if Masters is blinking back to a painful memory.

This is a good way to handle material that deals with horrific child abuse, and the "blink" device recurs throughout the book to great effect.

The heart of the memoir covers her training and competing — she was a rower first, until a broken bone in her back put an end to that, and then she became a skier, a biathlete, a cyclist. She has won more medals in the Winter Paralympic Games than anyone else — 14, plus three from the summer games.

Masters' achievements are amazing, but what is even more amazing is the attitude she has had apparently from birth. Living in the dark, freezing orphanage, where Masters is told repeatedly that she has been put there because she has been bad; where children are tucked so tightly into their beds at night that they cannot move; where there is not nearly enough food and what there is is rancid; where botched, painful surgeries are performed on her legs; where strange men ominously approach her bed in the middle of the night and press their weight on her and she feels searing pain — despite this life, she writes, "When I wake this morning ... it's with the same idea as every other morning: This is going to be a good day. It's a new day, after all."

This chipper attitude might not be credible if that was all there was to Masters, but as the book progresses — she is, almost miraculously, adopted by an American woman as stubborn and determined as she — other emotions come to play. Anger, for one, which for a long time fueled her workouts. Insecurity, which led her into an abusive relationship with a truly horrible boyfriend. Competitiveness, of course, which pushed her to victory almost in spite of herself. She would sink into what she calls her "pain cave" to push herself beyond what her body should be able to do.

Which, do you suppose, were the hard parts? All of them?

And yet this impressive book makes them seem almost easy.

Laurie Hertzel is senior editor for books at the Star Tribune. books@startribune.com

The Hard Parts
By: Oksana Masters, with Cassidy Randall.
Publisher: Scribner, 336 pages, $28.