Kevin Sinfield to run seven ultramarathons in support of Rob Burrow

Kevin Sinfield (left) is taking part in another challenge in aid of friend Rob Burrow (Danny Lawson/PA)

Kevin Sinfield will again push his body to the limit in support of friend Rob Burrow as he plans to run seven ultra-marathons in seven different cities across seven successive days.

Sinfield is taking on the challenge to raise money for motor neurone disease charities after seeing his great friend Burrow affected by the illness.