Q&A: The Hills Have Me Worried and What are Gear Inches?

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Q. Hi Gale. I'm really hoping you can help me. I'm a new triathlete from Brazil and I've entered my first Ironman. I've been using your 16-week Ironman training program and I am in fantastic shape thanks to you. The plan has been going very well and I was feeling eager and ready to race. Then my friends began to plant seeds of worry.

The place I train has smaller hills and I do the best I can to use the hills to prepare for my race. I'm only 12 days out from race day and everyone is telling me I need to quickly get into the hills--hard hills--to get ready for my Ironman that is on a very hilly course. Others are telling me I need small gear inches. I don't want to admit I don't know what that means.

I'm feeling nervous and confused. Can you just tell me what to do?

Last-Minute Help on the Hills

A. Thank you for using one of my training plans and I'm glad you've been having fun getting fit. At this point, with the race only 12 days away, any hill training you've done will work fine. Trying to cram more long workouts or harder hills into these final few days will do more harm than good.

If you have concerns about the hills, the best thing you can do at this point is to make some equipment changes. If you are running a small chainring on your bike (the smaller ring in the front) that has 42 teeth, you can reduce that ring to a 39. You can also look into your cassette gearing to include a large-toothed gear (27 or 28 teeth) on your rear cassette.

The gearing changes allow you to do more spinning up the hills rather than pushing large gears. This helps save your legs for a good run at the end of the Ironman.

The gearing change also changes "gear inches" that people have mentioned to you. What that means is with each full pedal stroke your bike will travel a certain number of inches. A smaller front chainring (fewer teeth) combined with a bigger rear cassette (more teeth on the biggest back ring) gives you smaller gear inches and your bike won't move as far with one pedal stroke; but that also means it is easier for you to climb the hills.

On the reverse side, if you are pushing larger gear inches going uphill it feels like weight lifting. Your legs move slowly and it is a struggle to turn the crank arms one revolution.

For example, a 39 x 28 front and rear combination will have you travel 37.6 inches on 700c wheels. On the other extreme, a 52 x 12 front and rear combination will have you travel 117 inches. You can do an online search for "gear inches" to see a full chart.

The other options include changes using mountain bike gearing, a triple chainring or a compact crank. These options are more involved and cost more as well. One of these options can give you even more gears on the low end (allowing you to more easily climb hills) and may be best for you in the future.

Talk to your bicycle mechanic to see what he (or she) recommends. You want to be able to put your bicycle in a low gear and spin up the hills, rather than struggling, standing up, or weaving back and forth across the road.

Let me know how it goes for you.