Doubles: more than mileage

# Doubles: More Than Just Mileage

## Unpacking Doubles

Doubles, in the context of running, refer to the practice of splitting your daily run into two distinct sessions. This is a strategy often employed by elite runners to increase their weekly mileage without adding undue stress on their bodies. But beyond the simple act of running more, doubles offer a range of benefits that make them worth considering.

## Benefits Beyond Mileage

Doubles are not just about racking up miles. They offer a different kind of physiological stimulus that can lead to better fitness and performance. When you break up your run, your body goes through the process of warming up, running, recovering, and then doing it all over again. This cycle prompts adaptations that help improve your endurance and recovery ability.

A study published in the Journal of Applied Physiology (https://journals.physiology.org/doi/full/10.1152/jappl.1999.87.1.201) found that dividing training into two daily sessions more effectively increased mitochondrial protein content and citrate synthase activity than a single training session. These enhancements are indicative of improved aerobic fitness.

## Reducing the Risk of Injury

Doubles can also help mitigate injury risks. Running puts a lot of stress on the body, particularly on the joints and connective tissue. By splitting your daily mileage into two shorter runs, you decrease the duration of continual stress. This strategy can be particularly beneficial for runners increasing their mileage or returning from injury.

## Enhancing Recovery

Beyond physiological gains and injury prevention, doubles can also aid recovery. After a run, your body initiates a recovery process that involves glycogen replenishment and muscle repair. When you run again later in the day, you kick-start another wave of this recovery process, potentially leading to better adaptation and fitness over time.

A 2016 study in the Journal of Sports Science and Medicine (https://jssm.org/jssm-15-176.xml) found that the timing of training sessions significantly affected muscle glycogen levels. Athletes who trained twice a day with a six-hour rest interval showed significantly higher glycogen storage than those who trained once a day.

## How to Incorporate Doubles

Adopting a doubles regimen requires careful planning to avoid overtraining. Beginners should start slowly, adding one double day per week and gradually increasing as their bodies adapt.

The second run doesn’t have to be long or intense. A short, easy run will suffice. The key is to listen to your body and adjust based on how you feel. Remember, the goal is to enhance your training, not to run yourself into the ground.

## Doubles: A Tool for Performance

Doubles are more than just a tool for increasing mileage. They offer unique physiological benefits, aid in injury prevention, and enhance recovery. While they require careful planning and adaptation, the potential improvements in fitness and performance can make them a valuable addition to your training regime.