A second entry, this time from Montreal. The topic: what foods to eat and why you need to eat them. I've lifted most of the following information from several websites, among them http://tunedintocycling.wordpress.com/2008/05/09/cycling-nutrition-the-basics-glucose-glycogen-and-carbohydrates/, http://tunedintocycling.wordpress.com/2008/05/10/cycling-nutrition-eating-on-the-bike/ and http://bccclub.org/documents/NutritionforCyclists.html. We will begin with why, and here we go:
The muscles you use to cycle - hour after hour after hour, day after day on this adventure – are energized by glucose. Glucose can be derived from fats stored in our body, but the metabolic process to do so is slow and demands considerable energy. So, although the fat that we have - some of us have more than others - is somewhat helpful to fuel long rides, it doesn't do the whole job. A more effective derivative for glucose is glycogen, and appropriate nutrition will assist in the production of glycogen.
After 90 minutes of riding, most of the stored glycogen in our bodies is used. Endurance cyclists need to keep producing glycogen as they ride. Although a new supply is in part made from those stored fats, most of it comes from what we eat and drink while on the bike – and the fastest way to create that is to eat plenty of carbohydrates. Why? Because carbohydrates break down faster than fats or proteins to produce glycogen. So carbohydrates fuel ongoing muscle activity, and stretch the length of time it takes to exhaust your supply of stored glycogen.
So what do you eat while on the bike? How much carbohydrate? Nutritionists generally recommend food intake during a ride should consist of 60-70% carbohydrates, 15-20% protein and 10-30% fat. The easiest way to ensure that balance is eating energy bars, the ones that are heavy on carbohydrates. We tend to use Cliff Bars – because they are popular, tolerable to eat - and we can get them at Costco! Try a few different energy bars - as long as their C/P/F balance falls in the above range - and discover which ones work best for you. Nibble constantly as you peddle, and try to eat one bar per hour. Dried fruits, sweet potatoes or yams, and low fat cookies are good as well. Remember to drink as well, about 8 ounces/hour.
We note that most of our cycling buddies follow the guidelines about eating while riding, but there are some who disregard them entirely and seem to do well. My cousin, Terry Manning, who cycled across the country two years ago, often stopped for a big burger and fries for lunch.
So, that's what you eat on the bike. but what about food pre-ride and post-ride? Our favorite pre-ride breakfast is oatmeal, with milk, brown sugar and two tablespoons if almond butter. But anything is good as long as it is carbohydrate loaded, low in fat and protein, small in amount and taken with fluids. After a ride, we make a point of eating protein asap, but when I read the following, I wonder if there is merit in emphasizing carbs again. I've lifted the following from http://tunedintocycling.wordpress.com/2008/05/11/cycling-nutrition-eating-after-the-ride/:
When you finish a long ride your glycogen stores are exhausted and you are very likely to have low blood glucose. Your body responds to the glycogen debt by going into overdrive to replace the missing glycogen. Excess glucose in the bloodstream is converted to glycogen and stored in the muscles and the liver. Under normal circumstances insulin is used in this conversion process. However, after an extended period of exercise when the muscle glycogen stores are exhausted, an abbreviated and accelerated glycogen-storage process kicks into gear that converts glucose into glycogen and stores it in the muscles without the need for insulin. This period of intense glycogen production and storage lasts for 30 to 60 minutes.
In order to take advantage of this brief period of accelerated glycogen storage, the system must have blood glucose that can be converted to glycogen. And there's the problem. When you finish a long or intense ride you are almost certainly low on blood glucose. Your system is ready to rapidly and efficiently replenish your empty glycogen stores but it doesn't have the glucose it needs to make the glycogen.
The solution is to flood your system with carbohydrates that can be quickly converted to blood glucose which will in turn supply the accelerated glycogen production and storage mechanism with the glucose it needs. Although the enhanced glycogen production mechanism will operate for roughly 60 minutes after exercise has stopped, keep in mind that it takes time for carbohydrates in the stomach to be broken down into useable blood glucose. Food you eat during the second half of that 60 minute window may still be in the stomach being digested when the enhanced glycogen-storage process ends. The first 30 minutes after you get off the bike are critical. If you are going to fully replenish your glycogen stores for the next day's ride, you must ingest enough carbs during those 30 minutes to flood your system with glucose. If you don't, it doesn't matter what you eat for the rest of the day; you will be building on a weak foundation and you won't have the glycogen reserves you need to ride with strength day after day. This cannot be stressed enough; you have to reload your system with carbs during the first 30 minutes after you get off the bike.
How many carbs do you need to eat during the critical 30 minutes? Current thinking holds that you should aim to ingest one half gram of carbohydrate for each pound of body weight during the 30 minutes after you get off the bike. This is easy to figure out; simply divide your weight in half and eat that many grams of carbs. For example, I weigh about 160 lbs so I need to eat 80 grams of carbs within 30 minutes of getting off the bike. There is also some evidence that combining these carbs with protein may facilitate the glycogen production and storage process. The recommended ratio of carbs to proteins is 4 to 1. Thus, at 160 lbs I need 80 grams of carbs and 20 grams of protein.
Eating enough food to provide this much carbohydrate in the first 30 minutes after you get off the bike can be very difficult. The 30 minute part is much more important than the specific amount of carbs and protein part. If you can't manage to choke down the full recommended amount, eat as much as you can, but make absolutely certain you do it in the first 30 minutes after you get off the bike.
All for now. Next up: fluids and electrolytes.
Marlie
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