Train low, compete high is a hot topic among competitive endurance athletes these days. Training low is suggested to be defined as training with about 50% of resting muscle glycogen about half the time we train. This can be done in different ways, by training with low blood glucose and/or training with low muscle glycogen. Training with low blood glucose would be similar to running a long run without taking any form of carbohydrates during the run. An example of training with low muscle glycogen would be to head out for a long run after a long overnight fast and without having breakfast before the run. You can imagine how many variations of the above examples could apply to achieve training with low blood glucose or muscle glycogen.
The glycogen content present in the body plays a huge part in how long we can sustain performance over a long event. In theory training low stimulates the body to signal different pathways that support energy metabolism. Training in a glycogen-depleted state can promote the body to be more efficient at utilizing fat and potentially spare glycogen during endurance exercise. Basically, it’s to develop a more efficient engine for endurance exercise.
It’s been questioned whether training low always offers benefit. For example, if we set out for a 16 mile run of which 12 miles is to be run at a demanding goal pace, performance during such a workout could suffer if attempting this workout in a train low state. Maintaining goal pace becomes more of a challenge without having the necessary fuel on board. Completing such a workout with sufficient fuel on board offers a positive training effect in maintaining this faster pace for a greater length of time. If we train greater lengths of time at faster paces will we perform better come race day?
A disadvantage of training low for less experienced athletes is neglecting to define what fuel sources are best played out in the race setting. It supports performance to train the gut in understanding what kind and amount of fuel to consume come race day. One who never eats breakfast or takes fluids, gels, and any form of solid food in training risks not tolerating such fuel during competition. Could training low all the time contribute to race day GI upset?
In addition, we know that consuming sufficient daily carbohydrates supports keeping cortisol levels within a healthy range. Training often in a low state could make it even more of a challenge for an endurance athlete with high energy requirements to keep up with daily carbohydrate needs. This may have a negative impact on performance such that chronically elevated cortisol levels can interfere with the body’s ability to recover and contribute to overtraining syndrome. Could training low too often contribute to injury risk or a suppressed immune system?
Good Sometimes – Not All the Time
Yes, training low does have advantages, but not all the time. A good general rule of thumb for those wanting to play around with the train low concept is to train low during low intensity workouts and train high during high intensity workouts. Keep in mind that training in this low state too often may interfere with our ability to train hard.
Here are some more tips for seasoned endurance runners to consider if interested in applying the training low concept.
- Avoid training low for hard workouts and races.
- Avoid training low when the immune system is down, such as fighting a cold.
- Limit training low when sensing early signs of inflammation, such as a bothersome hamstring.
- Avoid training low if battling Female Athlete Triad or amenorrhea.
Try not to let the urge to train low allow for a generally low carbohydrate diet to take shape.
Be sure to practice with fuel during workouts to know what is well tolerated for competition when it’s time to “compete high.”