Determine Your Century Nutrition Plan

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Whether you're embarking on your first century training program or your 10th, your goal is to cover the distance without bonking.

In order to maximize performance, it's essential to fuel yourself properly during training rides and racing, especially when you're riding longer than two hours.

More: Carbohydrates: Fuel for Your Cycling

As a nutritionist, I've found that many cyclists tend to overestimate cycling energy expenditure, causing them to overeat and gain unwanted weight during the season.

Furthermore, taking in too many calories during training can trigger a multitude of stomach issues (e.g., nausea, diarrhea, side stitches, etc.) and ultimately harm performance.

Below is a step-by-step guide to help you determine your total calorie burn during training rides as well as your target calorie replacement needs after about 90 to 120 minutes of cycling. Happy riding!

More: 10 Training Fundamentals for Cyclists

6 Steps to Proper Fueling

  • Step one: Determine your goal cycling speed.
  • Step two: Multiply cycling speed coefficient (see Table 1) by your total body weight.
  • Step three: Multiply step 2 by 60 minutes to determine hourly calorie expenditure.
  • Step four: Add 22 calories to step 3 for every 100 feet climbed during cycling event.
  • Step five: Multiply step 4 by 0.3 to determine minimum hourly calorie replacement demands.
  • Step six: Multiply step 4 by 0.5 to determine maximum hourly calorie replacement demands.

Table 1. Calculating calorie expenditure during cycling

Average Speed(mph) Coefficient
(cal./lb./min.)
15 0.0561
16 0.0615
17 0.0675
18 0.0740
19 0.0811
20 0.0891
21 0.0975
23 0.1173
25 0.1411

A Sample Case Study

Joe is a 150-pound athlete gearing up for his first Ironman. He's had issues with premature muscle fatigue and cramping during previous races which has led him to seek nutritional advice for race-day fueling. We used the guidelines specified above to help devise the perfect nutrition plan for his needs.

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