Strength Training to Improve Durability

It's something every runner strives for. "I want to finish strong".

Being able to cross the line knowing that you've emptied the tank at the right time and have been able to pick up the pace near the end is a rewarding experience. The alternative, dragging yourself over the line after slowing down is demoralising.

To achieve this sensation a multitude of factors need to be considered. Undoubtedly, you must have trained enough and at appropriate intensities to meet your goal. Nutrition, pacing and adjusting your effort to conditions on the day all play a part.

Richard Ringer winning the European Marathon Championship in 2022 with a perfectly executed sprint finish. Photo from Runners World.

We all think about getting ourselves to the start line in the best possible condition but what is being understood more recently is that our condition can change drastically throughout the course of a race. This is being termed "Durability". For example, if you start a half marathon thinking 4 minutes per kilometre pace is your threshold and judge your pacing from this, it's likely by the end of the race your threshold will actually be slower than this and you risk running above your threshold for longer than planned and "blowing up". Simply put, it is accepted that your running economy, Vo2 max and thresholds all get worse during prolonged running.

This is typically researched by testing a group of runners when they're fresh in a lab on a treadmill and noting markers of their fitness. The runners are then put through a block of challenging work and tested again to see what changes have occured when compared to their baseline markers.

One of these studies reports a decrease in running economy of 4.2% after 90 minutes of running and 5.8% after 120 mins of running. The drop in Vo2 max is even more drastic, seeing a 3.1% drop after 90 mins and a 7.1% after 120 mins. Clearly, figuring out ways to mitigate these decreases is attractive.

Research from cycling points towards accumulated years of training being important and anecdotal evidence from coaches and athletes highlights long progressive runs as being essential for building durability. The other area that holds promise for improving durability is strength training. This is being investigated by Michele Zanini who is an Italian former competitive middle distance runner now completing a PhD in applied physiology at Loughborough University. His most recent publication is a well conducted randomised controlled trial showing that a 10 week strength and plyometric programme can half the reduction in running economy during a 90 minute run (4.7% - 2.1%). The other key finding in this study was that at the end of the 90 minute treadmill test when asked to run to exhaustion at a pace corresponding to 95% of Vo2 max (bloody hard) the participants who were in the strength training group managed to improve their performance by 35%. Zanini estimates this equates to 5-10% improvement in a time trial or race performance.

The 28 participants of this study were male (lack of females was a noted limitation) and had 10k times of close to 39 minutes, this would put them in the "well trained" bracket. They were split into two groups, one group continued with their normal training and the experimental group completed two strength training sessions per week. These included two plyometric exercises and three strength exercises (back squat, single leg leg press and a seated isometric calf raise). They were encouraged to continue with their normal running training.

Other than the treadmill tests to measure durability all participants were put through a battery of strength, power and body composition tests. The running only group did not change significantly in any measure whereas the strength group improved all strength and power measures, improved whole body lean mass by 1-2% and reduced whole body fat mass by 11.5%. Overall body mass did not change significantly.

This study endorses the belief that completing strength work helps you in the later stages of races. It's something I hear a lot from runners I help with their strength and conditioning, "I just feel stronger near the end" or "I didn't feel my legs getting as tired". This study helps explain this intuitive sensation. The underpinning rationale for this is likely that you have increased your maximal force production capacity. This reduces the relative effort required to maintain your pace and costs you less energy. The type of muscle fibres you use can also change. Type I (slow twitch) fibres are the most fatigue resistant and are most heavily relied on when running. However, as the race goes on and these fibres fatigue or when you need to increase your pace you call on type II fibres. You have two types of type II fibres and strength work can help you shift from less efficient type IIx fibers to more oxidative type IIa fibers. These are less "expensive" to use in terms of oxygen cost. Strength and plyometric work can also increase tendon stiffness, which can help reduce the muscular contribution to running. Less muscular contribution also contributes to less energy cost.

Hex Bar Deadlift - Example of a strength training exercise that allows high force outputs

In practical terms, this is encouraging for runners. We have all experienced the boost in race performance from supershoes. These typically improve running economy by 3-4 %. If the findings here suggest that our running economy decreases by 4.7% after 90 minutes of running at around marathon pace but we can cut that to 2.1% with suitable strength work there is a real chance to make a meaningful difference to performances.

It's tempting to read a study like this and decide you're going to replicate exactly what they did for the strength work. It must be remembered that these exercises are picked because they are simple to coach and allow clear monitoring of loads being used. From listening to Zanini discuss this study on podcasts he's quite open about this programme fitting the study well but not necessarily being an optimal programme. More glute and hamstring exercises are lacking and the calf exercise is not practical for most commercial gyms. He also mentions the potential role of more traditional power based exercises like weighted jumps. One standout was his preference for the concentric phase of exercises being performed with maximal intent, this is something I have posted about before. It's a good way to ensure optimal motor unit recruitment for each rep.

The goal here was to introduce durability as a determinant of performance and explore strength training as a potential mechanism to improve it. This study is a promising start!

For anybody who has used the Running Buddy programmes the concepts discussed should be familiar. Plyometric exercises and exercises that allow you develop high levels of force for key muscle groups are the basis of each workout, particularly in the Loading Up and Gym Base programmes. I will happily discuss your training with you if you'd like to get in touch and I would recommend trialling the app for anybody who would like to see the types of programmes I promote.

You can download it here - Running Buddy Trial

*Using TRIAL50 will get you a month for half price.

Thanks for reading,

Patrick