So after the elation of the 20 minute run I am laid up with a horrid cold and hacking cough. I am worried about when to run again and working out when I'll be ok to do so.
It'll have to be indoors on the treadmill as my son is now at home for the holidays, which means I'll be making trips specially to run so it's more planned than my usual runs after dropping him off at school
What is the rule about starting again? I don't want to leave it too long...
I wouldn't run until my body felt that it could otherwise you could be worse off. You won't loose your fitness level so don't worry about that. Just keep warm lots of fluids and get well soon.
At least it's over before Christmas. 
Coming up to four weeks this weekend since I started this "cold". I have run twice in that time and it has not done me any good at all. Wait until you feel good again and certainly clear of any coughs or breathing difficulties. It is most frustrating, but there is no point exacerbating the condition. I had hoped to do parkrun tomorrow, but will definitely have to give it a miss until after Christmas.
Get well soon.
As everyone has said listen to your body it'll push you back if you push too hard. Make sure your temperature is down and make sure your cough is definitely a cough and not asthma. if in doubt I know you'll give your doctor a shout. take it easy and REST.
Sorry to hear that you are poorly. There's such a lot going around at the moment. Hope you feel much better in time for Christmas and as everyone else has said, the running will wait - concentrate on getting better first.
I agree with IannodaTruffle having had the same issue myself. My gp informed me that my oxygen levels had fallen when i had chest infection with awful cough and said no running till you feel better. To be honest i couldnt have run anyway!!!! You will not loose your fittness levels too much two months down the line i am doing my 30min runs with warmup and cool down walks with no problems. My speed is a little lower than it had been but hey who cares i am back out on the road!!! Get well soon.
On,y run when your well and able as you could end up doing more harm than good xxx you're fitness will be fine xxx
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