(L-R) Alise Post of USA (silver medal), Mariana Pajon of Colombia (gold) and Kiwi Sarah Walker (bronze) pose on the podium after the Elite Womens Time Trial Race at the UCI BMX World Championships in Belgium this week.

New Zealand's BMX golden girl Sarah Walker has returned from a career-threatening injury in the best way possible.

The Olympic silver medallist picked up a bronze medal in the time trial at the World Championship in Belgium, her first serious race since a nine-month layoff.

She is due to compete in the main elimination race today.

The podium finish is being hailed a great result for a first race back after and injury that left Walker with a shattered arm, damaged knee and a head injury.

During her recovery she contemplated retirement as she battled headaches, tiredness and forgetfulness.

After finally getting the all-clear by doctors, she began training but a planned comeback at the April BMX nationals in Christchurch was cancelled after she suffered another injury while mountain biking the week before.

Cycling New Zealand high performance director Mark Elliott said the third placing was a huge result psychologically for Walker.

"I think for Sarah it's been a massive step in confidence after being away for that length of time... the sport of BMX is a mental sport, it's a combative sport but you've got to be in a good state of mind."

While doing so well in the time trial was encouraging, the true test would come on Sunday when she raced against other riders shoulder to shoulder.

"It's a great step forward, but if she did the same today that would be amazing."

Walker was unavailable for an interview on Saturday as she prepared for her next race, but earlier said the race could not have gone any better.

"It's quite overwhelming," Walker said. "It's been such a long way back and I've had to go through so much.

"I had no idea how things were going to pan out. Today I was really happy with two good laps and after a long time off racing. After everything I've gone through, I feel like this medal probably means the most to me of all the medals I've won."

Sitting at the starting gate, Walker said she had focussed on getting the best start possible and visualising the track.

"It's never going to go perfect, but it was pretty close, So I was happy. It was nice to get the result because it's been a long time."