Running hills in a race is different than training. The way you approach hills is going to be dependent on the grade, duration and the length of the race. You want to get up the hill as fast as possible and are going to need to put in more effort. In races like XC or a 5k or 10k road race you want to push the uphill but not redline it. Longer races you stretch out that effort but are still putting in more effort. No matter what race you are doing you want to be able to push over the top of the crest of the hill and keep up the speed. On steeper downhill grades during a race you let go and let gravity pull you down trying to recover as much as possible. In training you keep it consistent and as many have said above on the downs you try to save the knees and ankles.
Lumps/hills/mountains? Can you see the top, depends on length/distance/incline and mainly what is the most efficient way of getting to the top for long races. Power walking or running with short strides and quick cadence. Stryd for me comes in handy here to ensure I’m not overdoing effort.
Downhill vary, if it’s steep short, I do the spinning a log method, back pedalling type stuff. Hard to explain but great for downhill, do the action of being on that log, spinning the log forward as you descend downhill… Terrain that isn’t too steep, take advantage of gravity, open strides, but don’t kill your legs with impact.
Oh no I think I might actually like running?
I started doing some trail running to supplement my cycling over the cold/wet UK winter and ended up entering a road half marathon last weekend and took 30mins off my PB from the last time I ran the same race in 2016.
I did a 1:28:06 which I’m super chuffed with. My quads are still killing me 3 days later - I assume because all my “training” was trails and they weren’t ready for the constant plodding of road?
So now I’m thinking I might actually like running? I would like to do a marathon but I’m sort of an all-or-nothing kind of guy.
Would a goal to run a sub 3 hour marathon be at all realistic if I were to do a proper 12-week training plan?
I’m thinking this would be a “next year” thing - Manchester Marathon is in April so April 2024 - start my training after Xmas?
Depends on how much you are willing to run and of you can stay injury free…
1.28 is a solid half!
I would argue that 12 week might be to short to train for sub 3, but you don’t know unless you try… I say go for it, you have absolutely nothing to lose.
I’d loose 12 weeks of my life 
Nah.
You will get a lot of fitness in those 12 weeks that can be use for cycling!
My experience is that the level and duration of soreness after a race is directly related to the volume of run before hand. 100 mi months, very sore. 150 mi months, kind sore. 200+ mi months, not that sore.
I think this 100% depends on your run volume so far and if you can build it to a reasonable level. 1:28 is on the slower end of someone doing 3:00 in the same training cycle (rule of thumb of M=2xHM + 10’). It does mean that the ability is there. If you keep consistent running and build some volume, a <3 marathon this fall or spring next year should be very doable, even if one 12wks from now may be out of reach.
Broke the 2hr for a HM on Sunday on an easy’ish training trail run, only looked at time as I approached 20km… first time under 2 hours in probably 20+ years, but I don’t go all out ever, maybe try that one day on a proper HM event… but I’ll never get under 1’30 for a HM, kudos for that… I know I’m doing a lot of easy miles but enjoy them all, haven’t pulled up that Garmin stat before, this is mine… 
Do regular HM’s and never sore, but as stated I never go all out so probably not a good study…
I have done 100 miles in one week
I used to do about 300 per month… But that was before becoming a triathlete
For the marathon i did last February, i think the max i did in one week was maybe 45…
With that I was able to do 3.12 on a hot and windy day with 12 weeks of training
You used to do 300 miles per week? 
Oddly, I know quite a few guys who have never run faster than 1:28:xx and have gone sub 3hr. Seems odd to me, but I chalk it up to them being diesels that can run one speed for a long time.
Month!
Jesus… dont post and drive children.
I’ve absolutely no reason to expect this is true for me though - if anything I would expect to currently sit the other side of the bell-curve with my low mileage to date.
Good to know that a sub 3 is a realistic aim if I were to train for it though.
Odd to me as well. 1:28:xx is just about the same pace as 2:59:xx, just for half as long (within day to day/race to race/course to course type of variations).
You have the bike fitness. You need to translate that into running fitness…
You MUST up your volume, sadly there is not way around it.
Your bike FTP might suffer some but not as much as you would expect.
I think if you can get your millage to high 40s low 50s… run 5 days a week, 1 speed day, 1 tempo and one long (maybe combine tempo and long)… and z2 cycle, for 16 to 18 weeks I have no doubt you can hit sub 3 on perfect weather marathon… with a similar schedule I was in shape for a 3:08 on the same course i did 3:12 on a with better weather (colder and less than 25-30 mph wind gusts going up a causeway). On a perfect course and day I think i had the fitness for a 3:05-3:06. That is with 14 weeks of training and only 1 20 mile run.
Interesting. Maybe they didnt train as hard or tried as hard on the half?
Stupid question, as far as you know, the 1:28 half, was it a stand alone race or was it during the marathon…
Some people use the half time as their PR if they have never raced a half by itself.
Reference bike fitness, I’ve dropped from 5 bike workouts to 2 a week (Threshold and Sweetspot) and now doing 3 runs a week. FTP has dropped by about 8-10%.
Heh… glad I’m taking it gradually then. My April plan is for 50 miles, and I’m trying to build up veeeeeery gradually to the Staten Island Half in NYC on October 8, then to the full NYC Marathon next year.
At least now I’m definitely seeing progression. My FTP just hit 213W (1.97 W/kg) which is my PB, I survived a 3x20 sweet-spot workout for the first time ever, and I’m now able to jog 5x weekly for a total of roughly 10-12 weekly miles.
I figured out that my issue is not excess weight, but rather that I’ve eaten so badly for so long that I’m already insulin-resistant. Changing will take much more effort, for a much longer time, than I thought it would… but as they say, direction is more important than velocity.
I did an FTP test about 2 weeks after the marathon…
Test was a total shit show… FTP came out like 216… but AI ftp said I was still on 236. So I split the difference and set it to 226…