I've been doing the c25k on my treadmill in the garage. On Thursday I did wk4r1 and kinda thought it was easy....so seeing as ive signed up for a 5k at the end of march i thought id try doing w4r2 outdoors. So this morning i loaded up my ipod and off i went....problem was It didn't go as planned. I was EXHAUSTED by the end. It is so much harder to run outdoors than on a treadmill. So have decided i need to switch to doing the program outside and retire my treadmill sessions. I think i might have to extend and repeat week4 just to get up to speed. I really felt like i had not completed weeks1-3. I have to say...i enjoyed the session much more. Running outdoors is less boring...there is more to look at and it was just a beautiful morning...chilly but not freezing. I did enjoy it more. I guess im an outdoor convert!
Treadmill versus Outdoors....outdoors is HARDER - Couch to 5K
Treadmill versus Outdoors....outdoors is HARDER
I could have written your post myself! I did exactly the same thing. My first outdoor run was horrendous! I had graduated but couldnt run more than 5 mins outside. Until I slowed right down. Then I was fine. Slow down. Then slow down more. And even more if needs be. Then you will do it!! And you are so right. Outdoors is so much better. How did I run 30 mins on a boring treadmill? I've never been on one since. Been outside 5 months now and love it. Even the rain and the dark!!! You will manage. Just slow down!!!!!!
hi and welcome 
i think the bigger percentage of us do probably run outside hopefully spring is coming and we are all looking forward to that
good luck with you runs now outside, see how you do and then decide about repeating or moving on
I did my first outdoor run today. I've done two 5k's on the treadmill and one outside now. Running outside is less boring, and harder, but excessively so. I tried to run at the same pace I always run at in the gym, and it seemed to work. The slight uphill sections were a bit of a trial, I'm never come across hills before!, but trying to avoid mud and dog poo gave me something to think about. Certainly it's different, but less different and there were fewer problems than I had imagined. Like a lot of c25k much of it is in the mind.
I am so pleased...why oh why do people choose to run inside when we are blessed with having a gorgeous World out there to enjoy. I am so pleased you have made the transition, yes it might be tough but you won't regret it 
A number of reasons. If someone is very big then it can be embarrassing to run outside (I did, but it was a BIG step to do that and actually put me off starting). There is are also practical reasons. In the winter I can't run during daylight hours so I feel safer on the treadmill. Also if my husband is out and I'm at home on my own with the children I can't just go out for a run. So with a treadmill I can run once they are in bed. Don't get me wrong - I will ways choose to run outside, but sometimes it is not possible.
I started on the treadmill too until wk4 and I think the hardest thing about running outdoors is judging your speed. Keep trying to imagine the speed you were doing on the treadmill and you will be fine. Slow and steady. Speed will come. Good luck and enjoy.
I think that there is a real issue regarding judging pace when running outside and this catches many out. I also think that when people run on a treadmill they keep it flat... The world isn't flat! When I run on the treadmill I put it on a program that varies the inline between 0% & 2% throughout the run - this made my transition to running outdoors easier.
I would also say the opposite is true - many who have ran only outdoors can struggle with the treadmill. I suppose the thing to remember that running outdoors and on treadmills is the same but different.
I would be scared to run on a treadmill!
Interesting to read the comments about judging pace outside. I have never run on a treadmill but one of the things that puts me off is wondering how you gauge your pace on a treadmill. The speed at which I run is determined by a lot factors and varies a bit from day to day. I have avarice idea of what it might be while I'm actually doing it but it is entirely based on feel. I don't see what it is in actual numbers until afterwars when I look at my garmin data. Whereas on a treadmill you are committed to an arbitrary pace you set at the beginning. I realise you can probably increase or decrease it as you go along but that seems very counterintuitive to me.
Ah, but isn't it more in that I've to set a pace and stick at a consistent pace?
My opinion is very much that they both have their positives, but they depend on opinion.
You are not committed to anything on a treadmill - the user has total control. What I like about the treadmill over running outside is that when lethargy sets in you don't find yourself slowing down as much. It is almost like a pace setter running beside you helping keep pace.
Like I say, both have ups and downs.
a vague idea not avarice idea. Wretched iPad and its insane autocorrect
So true! I'm making great progess this winter on the treadmill and can't run outside due to the freezing and snowy weather. I was able to run outside several weeks ago, chilly, but clear. I found the same as you--much tougher out there, but more to see. Looking forward to nicer weather to run outside all the time. Tredmill shmed-mill...much better outside.
I used to run on a treadmill many years ago, but did C25K entirely outside. I think treadmills are easier as they have a bit of "give" which the road doesn't. As everyone else has said, it's well worth making the effort to run outside, so much less boring, and all that fresh air and light is so good for you..
There are so many people on here saying 'running outside is better!' and I take exception to that. Running outside IS NOT better. Doing what you prefer is better for you.
Everybody doing C25K is diferent, but we all have one thing in common. We all were unfit and made the effort to start running. Whether we are doing it on a treadmill or outside or both we are all 'better' than we were when we started.
In terms of fitness or calories burnt running outdoors or on the treadmill neither is 'better'. They are slightly different in experience but that is all. People who state that running outdoors is 'better' are simply stating that they personally enjoy it. They may believe that everyone should be running outdoors, but that is nothing more than opinion.
Do not get caught up in this argument if you are a new runner, and if you are an experienced runner please don't state one is 'better' as this can be hugely demoralising and damaging to someone who is struggling.
For those struggling with pace running outdoors for the first time have a look online for apps (or podcasts) called 'running metranome'. Use it once on the treadmill to get the beat rights and understand how yo run with it. It wakes the transition to outdoors so much easier.
Whatever you are doing, be it treadmill, outdoors, on a track, round a park, along the beach, on a rural path, on the pavement or even running in circles it is SO MUCH BETTER than sitting on the couch.
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