Carbohydrate Timing for Health and Sports Performance

How are you supposed to time your carbohydrates?It should be more than clear now to see how important it is for athletes to consume the right amount of carbohydrates, especially those considered to be complex carbohydrates. To support athletic activity, the Certified Sports Nutrition Specialist should recommend that athletes eat a diet in which 8 to 9g per kilogram of body weight comes from carbohydrate each day. Considering a diet of 3600 calories, 2600 of these calories should come from carbohydrates. There is enough science and research to back up these recommendations for all athletes in training

So we need to be able to look at grams of carbohydrates consumed each day. In one study, swimmers were divided into two groups; one group ate a moderate-carbohydrate diet (43% of calories coming from carbohydrates); the other group ate a high-carbohydrate diet (80% of calories from carbohydrates). But in the end, there were no differences in swimming performance between the two groups.

One explanation for the lack of difference between the two groups might be that all swimmers were eating high calorie diets, averaging about 4,000 to 6,000 calories per day. They were also all taking in roughly 500g of carbohydrates each day. We know enough by now that this is enough fuel for strong performance – but it also happens to be about as much carbohydrate as muscles will hold or store when broken down into glycogen. Somewhere around 500 to 600g of carbohydrate (consumed daily) seems to be the limit of glycogen storage in muscles – to a point where muscles do not hold or accept any further glycogen. in this way we have to understand that there is an upper end limit on how much muscle glycogen the body can store. It’s when we over consume carbohydrates that things become more problematic. Once the bodys’ glycogen stores are full, the liver then turns the overflow into fat, which is stored under the skin and in other areas of the body. This is not conducive to athletic performance.

It should also be noted that the amount of glycogen that can be stored in an athlete’s body depends on their degree of muscle mass. The more muscular and athlete is, the more glycogen they can potentially store. Remember to use the formula described earlier for carbohydrate intake (8 g of carbohydrate per kilogram of body weight daily). Once an athlete has carbohydrate levels in balance, both you and the athlete should start seeing additional performance or strength gains.

There is a lot of misinformation about pre-workout carbohydrates. Whether or not they are good for your athlete depends on their sport and their goal. A strength trainer in a mass-building phase would fuel themselves with carbohydrates before and during their workout. The best timing recommendations for eating before exercise would be to consume a small meal of carbohydrate and protein 1-1/2 to 2 hours before working out. Ideally this meal should contain about 50g of carbohydrate (200 calories) and 14g of protein (56 calories). For athletes who are training to lose body fat, suggest forgoing any pre-workout carbohydrate drinks – but be sure to still suggest that the athlete consume some pre-workout carbohydrate/protein snack. The reason for not consuming a pre-workout carbohydrate drink is to encourage the body to tap into its fat reserves for energy. The only potential problem with this strategy is that the athlete may run low on energy during a training session but if overall weekly carbohydrate intake is still maintained within an ideal range, fatigue can be minimized.

During training sessions, glycogen is pulled from storage to replace ATP. You should remember that ATP is broken down in a series of chemical reactions and the energy released from this breakdown enables muscle cells to do work. During training, the glycogen and muscles progressively decreases and in fact an athlete can deplete as much as 26% of the stored muscle glycogen during high-intensity training sessions.

To encourage recovery after a workout or training session, it is essential to replenish muscle glycogen. If your athlete is able to replace depleted glycogen at the onset of the recovery period, the harder they will be able to train during the next workout. There are three critical periods in which to feed muscles with carbohydrates.

How Should You Eat After a Workout?

Immediately after a workout, when blood flow to muscles is at its highest, it is ideal to introduce new glycogen into the body because muscles are most receptive to producing new glycogen within the first hours after a workout or training session. During this time muscles are also more sensitive to the effects of insulin and insulin promotes glycogen synthesis. The best type of carbohydrate to consume post  workout is one considered high-glycemic. The higher the number assigned to a food on the glycemic index, the faster it converts to glucose. Ideally these would include carbohydrates such as those found in sports drinks, raisins, bananas, or even potatoes. All of these items are relatively high on the glycemic index (G.I.).

Every two hours after a workout, your athlete or client should continue to consume carbohydrates that are high-glycemic until approximately 100g have been consumed within four hours and a total of 600g within 24 hours after a training session. This equals roughly 40 to 60g of carbohydrate per hour during recovery. The CSNS should also be aware of the drawback to consuming high glycemic index foods because of the potential undesirable surge in blood sugar levels. iif the pancreas should respond to over secreting insulin to remove sugar from circulating blood, then blood sugar levels can drop to a low enough level to make an athlete feel weak or dizzy.

Low glycemic index foods can counterbalance this scenario by mixing and matching low and high-glycemic foods into your athlete’s diet. This will help an athlete to maintain a more steady- state with blood sugar levels.

Throughout the week the CSNS should encourage carbohydrate replenishment to maintain glycogen stores with a relatively high carbohydrate diet from week to week. If your client is an endurance athlete, this is even more important because increasing the amount of glycogen stored in muscles just before an endurance competition can mean the difference between victory or second place.. With more glycogen available, your client/athlete will be able to run, cycle, or swim longer before fatigue sets in and therefore gain a competitive edge. When done properly, carbohydrate loading works wonders for endurance athletes.

Your clients eating strategy should be high in carbohydrates on a daily basis, but this is not the same thing as carbohydrate loading. Some competitive bodybuilders have tried to practice carbohydrate loading mixed with periods of carbohydrate depletion, with the thinking that more muscular definition will show with carbohydrates depleted. Keep in mind that bouts of carbohydrate depletion can actually result in the loss of hard-earned muscle.

Learn about becoming a Certified Fitness Nutrition Coach or Sports Nutrition Specialist.