A British ultra runner has been candidly photographed pausing during a grueling 106 mile (171km) race to breastfeed her three-month old son.

Sophie Power had just stopped after 16 hours of running to feed baby Cormac at a rest stop on the epic Ultra Trail Mont Blanc race when the picture was taken.

Runner Mrs Power - who logged 112 miles during the event -completed the monumental route that crosses Italy, France and Switzerland in 43 hours and 33 minutes.

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British ultra runner Sophie Power has been photographed breast feeding her son during a grueling 106 mile (171km) race across the Alps. She logged 112.4 miles during the event

The mum-of-two usually feeds every three hours, but it took her a testing 16 hours to reach Courmayeur, in Italy, where baby Cormac was hungry and waiting

Mrs Power's race was recorded with Strava, a social networking site for athletes. Her route (pictured) and stats showed she has a moving time of 43 hours and 33 minutes burning 15,950 calories

In the touching image the mum who is a co-founder of Airlabs - a start up creating clean air zones in cities - can be seen with her baby in one hand and a breast pump in the other.

The runner and mother of two usually feeds every three hours, but it took her a testing 16 hours to reach Courmayeur where her baby was hungry and waiting.

Before she reached him, she was met by her husband at every aid station along the route, where he would hand her a breast pump and ferry back the milk to their baby son.

She said: 'Oh my god I was in agony! Cormac usually feeds every three hours and it took me 16 to get to Courmayeur where he could first meet me so I was hand expressing everywhere I could en route.

'I was so relieved he was hungry!'

The mum shared this picture with her family after the race, saying she'll never forget crossing the finish line

The route 171km (106.2m) route goes through France, Italy and Switzerland. It is widely regarded as one of the most difficult foot races in the world

What is the Ultra Trail Mont Blanc? The run takes place once a year and was held between August 27th to September 2nd this year. The route 171km (106.2m) route goes through France, Italy and Switzerland. It is widely regarded as one of the most difficult foot races in the world, and one of the largest with more than 2,500 starters. The race costs 250 € to enter. Due to the tough conditions 'heat-wave', 'winter' and 'bad weather' kits are part of the obligatory equipment. Advertisement

Mrs Power - who is a member of Strava the social network for athletes - had to take the race slow and steady and made subtle changes to the way she ran to cater for the fact that she was breastfeeding.

She said: 'I couldn't raise my heart rate too much as my body isn't primed to burn fat and I couldn't fully run downhills to protect my pelvis.

'In a typical race I would get in and out of the aid stations as quickly as possible but here I had to focus on keeping down enough food for me and for Cormac, and resting.'

She also believes that keeping active and maintaining a healthy lifestyle during pregnancy is really important.

She said: 'During pregnancy, it felt like all the advice was to put your feet up and get fat, as anything else was taking a risk.

'This is not the best way to prepare for motherhood - staying fit, healthy and strong is so important and how you can safely do that needs to be talked about more.'

Mrs Power has logged an amazing 273.3m (439.8 km) over 27 races on Strava so far this year. The site says she has spent more than 76 hours running in 2018.