Hi Jane,
Interesting topic for your presentation. In my experience running most definitely has a positive impact on mental health and I know that my GP would agree with that.
In 2009 I wen through a very stressful time at work and in combination with a lot of stuff happening personally that year, I ended up signed off with clinical depression and being prescribed anti-depressants. I stopped going out running as I had horrendous guilt - if I was fit to go out running I should be fit to go to work, but I wasn't. My main fear was that I'd be seen by colleagues or work associates.
In the end, I was only signed off for 3 weeks (followed by 2 weeks holiday) and it was thanks to from my running buddies that I did get back out. My GP had suggested going out for walks at least, a walk a few times a day. Again, the fear of being spotted made this difficult. Then a colleague that I was close to came to visit and made me realise that if I wasn't fit to meet people socially I most certainly wasn't fit for work (I teach).
That gave me the impetus to go out of the house without guilt, initially to walk round the block, then for trips to the supermarket. My friend persuaded me to join her for a weekend run, and I did of course bump into a colleague! I think the fact that her kindness had tears silently streaming down my face would have reassured her I wasn't skiving! She was the soul of discretion and I never heard anything more about it.
I took my time and started getting out more. My GP was delighted when I went back to work and shortly after decided to sign up for a marathon - my rationale being that I would have to make time for me & my training rather than focusing solely on work and getting dragged down.
I continued to run, stopped the medication after the marathon and felt well for a while. I ended up running another 2 marathons that year. Then I had a dip, was diagnosed with anxiety and ended up on medication for another year. Interestingly enough, although I struggled with many things at this time, such as going on crowded trains, busy places or flying, one thing I could still cope with was running races and this was a good confidence builder.
Finally, nearly a year ago I managed to come off the meds completely. I have found running to be a saviour in so many ways. I've got good friends through running and they've been very supportive of me. I've also had great support from someone on the RW forum who has had similar experiences and has been an e-mail buddy, allowing me to share things that I wouldn't share with friends and providing support and encouragement.
I now use my running both as a social thing and almost as a form of meditation. If I've had a bad day, I'll run and think things through, or just run to think of nothing. It makes me feel good and I'm certain keeps me healthy, both physically and mentally.
Hope this all makes sense - any questions, just ask! Good luck!