Strength Training for runners & cyclists : pros & cons

There is little doubt that Strength & Conditioning workouts are very much in vogue with runners and cyclists. But, as Endurance athletes, it might actually be counter productive to spend time in the gym? As with all things fitness there is no single definitive answer, so in this post I will discuss some considerations and…

There is little doubt that Strength & Conditioning workouts are very much in vogue with runners and cyclists. But, as Endurance athletes, it might actually be counter productive to spend time in the gym? As with all things fitness there is no single definitive answer, so in this post I will discuss some considerations and hopefully help you reach a more informed conclusion as to the best strategy for you.

Let’s Be Clear

Before considering the pro’s and con’s it may help to be clear about some terminology, some basic concepts and motivation for doing S&C.

A good question to ask yourself is what do you hope to achieve by including strength training? As an Endurance athlete, your performance is much more likely to be limited by aerobic fitness than strength. Perhaps you wish to make your “legs stronger? But to achieve this a movement pattern that simulates running (and all it’s subtle nuisances) might be a better way to go… Squats, lunges and leg press will all increase leg muscle strength; but I have not seen a runner or cyclist use a squat or lunge pattern whilst running or cycling… Where as super slow long hill reps will also build leg strength and conveniently using the *exact* movement pattern used in the sport you are training for.

You might wish to be able to hold an aero tuck position on a bike for three hours without crippling fatigue. In this instance simply holding that position for torturous periods of time is not an effective way to improve strength! But using appropriate shoulder and back exercises would be beneficial. Being clear as to the outcome / adaption you are seeking is vital.

Before moving on we should also differentiate between “strength” and “conditioning”. The former involves VERY heavy weights and protocols designed to create muscular growth; the adaption / improvement being the ability to “explosively contract” a muscle creating a very high degree of force for a VERY short time (a few seconds) with many minutes of rest before being able to repeat this. Conditioning is about much lighter resistance (weight) but repeating a movement pattern many times; improving elasticity, tendon strength, range of motion. But these movement patterns may, or may not, have any material bearing on the movements associated with your sport. Again be clear about what you feel you are trying to achieve.

It is too simplistic to say “strength” or “stronger”; you must break that down into what type of “strength” and to enable which movement in which way.

The Interference Effect

Not only could “S&C” be largely a waste of time, it could actually be counter productive to improved performance in Endurance events. How might this be the case?

In 1980 a chap named Hickson published a paper “Interference of strength development by simultaneously training for strength and endurance”. Over the course of ten weeks, three groups of recreationally active volunteers trained in different ways. One group did only endurance training, another did only strength training, and the third did the same programs as both the endurance and strength training groups, separated by approximately two hours of rest.

The strength group consistently improved their maximum strength over the course of the ten week study, and the endurance group improved their VO2 max similarly. Neither of these two results were particularly surprising and completely in line with what you would expect. However the concurrent training group initially improved both their strength and VO2 max, but after seven weeks into the study, strength improvements levelled off and then decreased. This eventually became known as the “interference effect.”

Hickson noted that it may be “deleterious” for strength athletes to undertake simultaneous endurance training due to the interference his study design showed. He also points out that there may be “little to no benefit” for endurance athletes to undertake simultaneous strength training.

Strength Training Can Impede Aerobic Gains

A more recent publication  (“Sub-cellular localisation and fibre type dependent utilisation of muscle glycogen during heavy resistance exercise in elite power and Olympic weightlifters” Hokken et al.) looked at glycogen depletion in elite power and olympic weightlifters who performed a high intensity lower body strength session. The workout was 4 sets of 5 squats, 4 sets of 5 deadlifts, and 4 sets of 12 rear foot elevated split squats. Muscle biopsies were taken before and after the workout in order to assess glycogen depletion. Muscle glycogen was depleted by 38% on average, but could be greater in some specific locations inside the muscle fiber.

As you will already appreciate muscle glycogen is a limited resource in a muscle, and can take days, rather than hours, to fully replenish. Glycogen depletion after a strength workout can greatly affect your ability to complete endurance training workouts effectively, to nearly the same degree as one would see in an exhaustive endurance session. However the adaptions from an intense strength session will (potentially) not be as beneficial as those from a cardio / endurance session.

There appears to be clear data demonstrating significant reductions in performance for several days after heavy or high volume strength training. Particularly the ability to complete extensive threshold work like FTP and tempo sessions. The intensity or duration can become difficult or impossible to maintain. Other research shows that muscle glycogen content is significantly correlated with endurance capacity. Again, this is no great surprise.

For runners & cyclists, improving performance and endurance capacity means doing high quality aerobic workouts. In essence the old fashioned adage that if you want to be a better runner you need to run.

Recommendations & Summary

To repeat my opening point; there is no single clear cut definitive answer! Can “Strength & Conditioning” be helpfully to runners and cyclists? Yes, I think it can. But it is a little more complex than going to a gym “now and again” and “having a go” with some dumbbells and resistance machines… My top three suggestions to help you get the most from “Strength OR Conditioning”:

  1. Timing. Think about when in your training to use S&C and when to cut it out. Factors to consider are as you progress through your plan your training should become more specific to the event you want to excel at. Will you need to do 20 Goblet Squats every kilometre? It might be that you want to do more S&C in your Base phase. Then within your weekly plan, when should you be doing what (remember muscle glycogen?).
  2. Purpose. Understand that your body is a complicated interconnected set of systems. Running quickly requires more than having fine Glutes or Quads (not that there is anything wrong with those!!). Posture plays a part, arm drive is important, proprioception matters… and so on. So actually just going out “running” might not be the best way to develop and train the peripheral systems associated with “running”. Similarly, a cyclist needs more than the Calves of a Greek God(dess) and Hamstrings that you could tow a truck with!! Shoulders, core, lower back and even neck all play important roles in providing a stable platform for your legs to drive against and for you to stay in an un-natural position! Think about the value you want to get from a particular exercise and how it contributes to “making the boat go faster” as well as the price of doing it. It might be that conditioning can help you remain injury free by improving a weak spot?
  3. Method. Think carefully not only about the exercises you choose but also the way in which you perform them. For instance there must be hundreds of different shoulder exercises – but they will target different muscles in different ways. Do you want to isolate a muscle or do you want to perform compound movements? Are you trying to increase the size of a muscle (remember you will probably have to carry your new “friend” up a hill!) or do you want to increase the force of a contraction (perhaps to crush a walnut at an aide station as a party trick?) Or do you want to increase the tone of a muscle group? This sounds similar to “Purpose” but the point here is that how you do a particular exercise (Method) will change the result you achieve.

Short answer: Yes add conditioning, But do it with your eyes open and thoughtfully.


Ed Stivala is a Personal Trainer & England Athletic qualified Coach. His practice specialises in performance coaching for runners of all levels, as well as general fitness coaching for non-runners. He also holds qualifications in Cycle Coaching, Nutrition and Swim Instruction. 
When not Coaching, he competes in Duathlon and plays golf very badly!


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