Strength Training for the Endurance Athlete

Why include strength training?

A key part of the endurance athlete’s off-season is the inclusion of a strength training program. There a multitude of benefits to incorporating at least one session per week such as:

  1. Improving the strength of slow twitch muscle fibers with the aim of reducing the burden of contribution from fast twitch fibers which are glycogen hungry, quick to fatigue and slow to recover.
  2. Improving lean muscle composition leading to more muscle fibers contributing to power.
  3. Correcting imbalances between the right and left leg, or between upper and lower body thus improving exercise efficiency.
  4. Injury prevention – strengthening the ligaments and tendons around the large muscle groups can reduce the likelihood of injury if there is a sudden change in power such as in sprinting.
  5. Decreasing or preventing the loss of muscle mass in older athletes who require a greater stimulus to achieve muscle growth

Whatever your reason for integrating a strength program it’s important to understand what the goal of the session is and how it will impact your endurance training adaptations. 

If the goal is to build muscle (hypertrophy) there are key stressors which will lead to this – namely adequate essential amino acid intake and resistance training. 

If your main goal is to simply improve endurance capacity the key adaptations you’re looking for are enhanced mitochondrial mass, improved fat and glycogen combustion and increased capillary density.

So what happens if your goal is both to build muscle AND improve endurance.

We asked elite personal trainer and endurance coach to a host of international triathletes and cyclists, Barry Monaghan, what to consider when doing concurrent training sessions – aka double days

“Interestingly, if you get the timing wrong, endurance training can actually diminish the gains you would expect to see from a strength training program. Better known as the interference effect, it’s due to the response from endurance training inhibiting those required for increased muscle mass. As an endurance athlete you need to decide what the priority is from each session and integrate accordingly”

High intensity endurance and resistance training – before or after?

The answer depends on how much time you’ve got.

Over 3 hours between sessions?

After a high intensity endurance session, a rest period of at least 3 hours should be given to allow lactate levels and signaling proteins, which interfere with muscle building, to return to baseline. 

Less than 15 mins between sessions?

If, however, you’re short on time and have less than 15 minutes recovery between a high intensity endurance session and resistance training, it may be beneficial to begin with the resistance session. 

There will be a slight blunting of the response to the resistance training but not as much as if you were to complete the high intensity endurance first.

Low intensity endurance and resistance training – before or after?

Commencing low intensity endurance training with low glycogen content can enhance endurance adaptations. This has the effect of increasing the training response which leads to increased mitochondrial mass and improved fat and glycogen burning. This would optimally be completed in the morning following an overnight fast where liver glycogen content will be lowest.

Provided adequate nutritional status is achieved in the hours between the endurance morning session and afternoon resistance session – the stimulus for enhanced muscle protein synthesis will be primed for strength training.

In summary 

It’s easy to see the benefits to a well thought out strength program especially for older athletes who are seeking to prevent the loss of muscle mass. The complexities lie within timing endurance and strength training to avoid conflicting adaptations. 

The key aspect which will influence these adaptations to either exercise is your nutrient intake. The optimum total, type and timing of carbohydrates, fats and protein is the foundation of any endurance performance nutrition program and will form the bases of the athletes individual coached program.

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