As a dedicated cyclist I only occasionally do runs to mix the training up a bit or to avoid doing nothiong at all, when on vacation or on the road without a bike.
The problem is with the unregular runs I alway end up with extrem sore muscles preventing me to do any workout at all for several days. As long as I run at least once or twice a week I don’t have that problem… But when I start running again after a longer break, I always have extreme sore muscles, even after the shortest and easiest runs.
Is there any suggestion as to what to do about it? As long as the cycling season is running and I train according to a training plan, I simply don’t have the time to do regular runs. But as the off-season approaches, I always suffer from the sheer expectation of sore muscles after the first run in the off-season.
How short is a short run?
I recommend doing some dynamic stretches to get you going.
Best thing to do is set out at a light jog for 5mins then stop to do your dynamic lunges (toe reaches, high knees, heel kicks, lunge & rotation, squat & overhead reach, etc) and then get going into your run.
When you finish, a few minutes to walk off the legs to avoid blood pooling will also help and then some static stretches or a yoga video
This! 
If you’re like me, I always end up with sore soleus and calf muscles when I restart after a break from running. Those muscles aren’t really heavily used during rides, and certainly not used to the impact of running.
First, the obvious thing is keep running 1-2 times per week but try reducing the duration/intensity. I’ve been good about doing this so far this year but have kept my runs short to allow my cycling not to suffer.
Second … this summer I started “allowing” myself to do walk-run sessions. If you can bring yourself to do this (and you should), you can play with the ratio of walking to running to control the duration and intensity. It’s nice to do these workouts and not feel as beat up from the impact. These are sometimes more enjoyable than normal runs, once I set my ego aside.
Lastly, the other thing you can do is strength work on your lower legs … seated and standing calf raises to strengthen your soleus and calf muscles. I’ve been meaning to do this but strength and mobility work always seems to take a back seat, but shouldn’t. 
Good luck!
Ultimately, running requires a different type of muscle contraction called an eccentric contraction that cycling does not use. Eccentric contractions are effectively lengthening movements of the muscle that cause tearing and damage to the muscles that result in soreness, typically peaking 24-48 hours after exercise. Strength training also includes eccentric muscle contractions when you lower a weight against gravity, which is why strength training and running (as well as downhill skiing among other movements) cause much more soreness than cycling does.
There’s something that is know as the “repeated bout effect” with eccentric muscle contractions that after you’ve done a movement that gets you sore, if you continue to repeat a similar stress on the same muscles the amount of damage and soreness will be significantly less than the initial stressor.
In a practice sense, the protective aspect of the repeated bout effect lasts about 1 up to 2 weeks. If you were to perform strength training consistently, you’ll have less exercise induced muscle soreness when you run. Also, if you run about once a week you’ll maintain a reasonable level of protection.
Personally, I run for a mile or two about once a week to be able to maintain a little bit of protection from the soreness and maintain some bone loading stress. Keep in mind, though, doing something different - like an uphill and downhill hike or go water skiing - there’s a slightly different type of stress and therefore you can still get sore from the new activity/exercise!
Thank you, coach.
Can you indicate a day in the training plan that we can integrate running?
For example, a day when you do a neuromuscular workout or endurance?
Thank you Neal for this very insightful explanation. I don’t want to overstress this thread but the question left for us Sufferlandrians is the same one @MikeSh raised: Where should such a 1 - 2 mile run should be fitted in when being on a training plan. On rest days? Or before certain workout types, maybe as a warm up?
Thanks a lot and keep up the good work with the Sufferfest!
I also want to hear from the coaches on this one.
My approach this summer has been to try and get my runs done on the same days that I do strength work and/or low cadence cycling rides like G.O.A.T or Power Station, usually to be followed by an easy or recovery day.
Hi all - an ideal place that I would encourage adding a weekly (or so), short run is as a warm-up for a strength training session. Another good alternative would be either in the morning of a day that you’ll be doing a more intense session later in the day, or vice versus (intense session on bike in the morning, then the short run in the evening.)
If you’re considering trying a multisport event (Triathlon/Duathlon) in the future - then definitely throw that run in after more intense cycling session to get a feel for what it takes 
It would be great to be able to integrate running with the cycling training plans, like yoga & strength. I’m not looking to train for a triathlon, but would like to include a little running.