katie shanahan reports.ootballer jordan nobbs was on the road to a world cup. but that all changed in november. she suffered a serious knee injury, tearing her acl. she was playing for arsenal at the time and while they could have been other reasons, she thinks there was one thing that stood out for her. she had just started her period. eye was very tired leading up to that week. eye was on the first day of my menstrual cycle. and, you know, i'm not one for saying it was because of that, but the facts on how many women have done their knee and been on their mental cycle has been very high. so, you know, i don't know if it was down to that but it was a very high factor —— menstrual. it was down to that but it was a very high factor -- menstrual. so is there a potential link between periods and injury? emma eros is a physiologist with the english institute of, working with olympic and paralympic institute of, working with olympic and pa ralympic mascots institute of, working with olympic and paralympic mascots

as part of the bbc‘s change the game season, katie shanahan has been finding out more.rdan six months agojordan nobbs was on the road to a world cup. but that all changed in november. she suffered a serious knee injury, tearing her acl. she is playing for arsenal at the time and they could have been other reasons but she thinks there was one thing that stood out for her, she just started her period. i was very tired leading up her period. i was very tired leading up to that week and i was on the first day of my menstrual cycle and imean, i'm first day of my menstrual cycle and i mean, i'm not one to say that it was because of that because, you know the fact on so many people have been on the menstrual cycle and injured the knee is very high. i don't know if it was down to that but a very high factor. 50 is there a potential link between periods and injury? emma ross is a physiologist with the english institute of sport working with olympic and paralympic athletes. i went to meet her

katie shanahan, bbc news. it isa it is a really interesting subject.octors, how closely monitored were you when you are playing? it was a simple thing of every morning before we woke up we would have about 20 questions, your resting heart rate, the colour of your you're in, how fatigued you are, muscle soreness, and at the very end it said yes or no, was a day one of your period and you click yes or no. so the coaching staff, namely the legal stuff would have a clear indication if it was the first day of your period and a pa rt the first day of your period and a part of your cycle. what did they do differently if it was? if you had a gym session they would lower down the weights, you would do less turning of doing a speed agility session. just because there was a bit of research to say actually, you are more susceptible to getting ligament and soft tissue injuries in that part of your cycle. did you find that it would make a difference your levels? definitely. even the little things, just knowing that the staff knew. a few days before, you know, you ge