For the first time since I began preparing for the London Marathon my training has been unexpectedly turned upside down.
A nasty head cold which has left me feeling as though there is a cork stuck halfway down my throat.
I'm struggling to breathe doing everyday stuff so I've not even attempted to do any serious running.
Steve has been restricted to wrapping up well for long walks
And, if that was not enough, during the last long run I managed to complete I got my first blister of the campaign.
Up until now I have been finding the running enjoyable. I've been following a programme and merrily ticking off each training session as it goes by.
Now, I've run into problems and I'm looking at the sheet in front of me and it's got nothing on it.
I feel very frustrated but I know if I go out and do some serious exercise I will probably make myself worse - and that could even put the marathon itself in doubt.
It is best not to try and push on through with any training programme if you are injured or ill. The chances are you will only take longer to recover.
It is better to do some form of exercise and I've been doing plenty of walking to breathe in the fresh air and get the system moving.
There is a science to training for the marathon but it's not exact
Because I was a serious athlete I know how important looking after your health is. You're better off being 90-95% fully fit before getting back into training.
I found it was actually more important to be fit for training than for the races themselves because if I couldn't train then I was not going to be the right calibre of athlete for competition.
But to get back straight back into training and doing every session - well, that's not sensible either. There is a science to training for the marathon but it's not exact.
I'm hoping to make a low-key return to training this week and according to my programme I have to do a 13-mile endurance run.
I'm confident I will be able to complete the distance but, even if I'm feeling better, I won't go out and attack it, I'll still run within myself.
Then I should be back on track and running reasonably well again so I can complete the marathon.
This year Steve will donate all the proceeds from his London Marathon efforts to victims of the tsunami.
Steve will be writing a regular column on the ups and downs of his marathon training for the BBC Sport website.
He will be raising money through the Steve Redgrave Trust which supports the Association of Children's Hospices, the Children With Leukaemia charity, and the Trust's own project which aims to provide inner-city schools with rowing equipment.