At the Tampa Riverfront CX races this weekend, the course designers took advantage of the park's man-made hills to provide several big run-ups (some grassy, some packed earth with a semi-loose surface). After several attempts in practice (including numerous falls) I found there was only one that I could confidently ride. The others seemed either too risky or took more effort for me to ride than to run.

So during the race (Masters 45+) I noticed that I was just about the only one running the run-ups. Other riders seemed to have little problem riding them, so now I'm wondering "what's my problem?" My low gear is currently a 36f:26r. I could switch to a 12-30t cassette, but I can't help but wonder if spinning a 36:30 would be slower than running? I'm a small rider (5'7", 145lb) and I've only been cycling a little over a year, so I have a *long* way to go before I'm as strong as most of the other riders. Perhaps I just need to leave the bike as is, suck it up and keep running the hills until I build the necessary strength. If so, any suggestions (such as specific interval workouts) for building up my short duration peak power output?

Find steep, short hills, ride them over and over.

Are you coming to a stop because you can't push the pedals or because you're losing traction? Regardless, I would say you probably need to be going faster as you come to the hill. It's amazing what a little momentum will do.

do whatever is faster/easier/takes less out of your legs. right now it's running, but as you get stronger, it may be riding. or maybe not, depending on the particular run-up. don't worry much about what the other riders are doing necessarily...the person in front of you might be going faster by riding up a hill and not having to dismount/remount, but they may have just killed themselves and saved nothing for the short, flat section right after, that you can now crush it on because running took less effort.

Agreed. I ride a SS so I have to run up more than the geared riders, and if it's short/sandy/muddy/etc., I usually lose less time than you would expect.

Correct. Same goes for deep sand, mud bogs, etc...

Also, whether something is better to run or ride can vary from lap to lap as traffic thins out or the course gets more chewed up.

at 145 lb, you should have an easy time riding up the hills, it's the big heavy guys like me that have the problems . . . +1 on momentum leading up to the hill, concentrate on building speed well before the hill. you should be at top speed coming into the hill, keep you rear wheel weighted when you stand. just watch out for traffic up ahead, might need to pick a different line depending on who is climbing in front of you.

I think lack of momentum was a significant factor. I would find myself at near zero cadence where I couldn't turn the pedals and still keep the bike stable. As a Florida roadie, I have no experience on steep grades so I was definitely intimidated riding at speed towards what looked to me like a big grassy wall

Do you have levees? Those are great to practice on. They're not long, but they are pretty steep and usually have uneven surfaces to give an extra challenge.

Another thing to try is getting into a bigger gear as you start at the bottom of the hill. I know you're thinking a lower gear is better for climbing, but a higher gear builds momentum quicker. This is especially true if you've just come around a turn or something and need to get some speed in a hurry.

The other thing I've found helpful on short punchy hills is to gradually come out of the saddle as you go up the hill. Start out seated and then stand on the pedals as you get toward the top. It helps with the low cadence mashing.

Of course, sometimes you just need to dismount. If you can get comfortable dismounting on the hill just at the moment that you lose momentum that can save you some energy.

. . . if the goal is learning how to climb a hill, there is no shame in gearing down till you develop the skill and strength.

You will always lose time when you have to get off the bike. What kind of gearing are you running? I have cyclocross gearing in the front and sram wifli in the back with a 32t cassette. I find that I am able to comfortably spin up all steep sections with this gearing. I would also recommend trying out some steep technical sections on mtb single track to practice handling, balance, and track stands.