Strength training. We all know it’s important… right? Strength training has been accepted among the endurance community as an important component of training. It’s assumed that if we lift weights it will somehow benefit performance. But how? How much strength training is needed? What type of strength exercises? These are all questions that still exist among endurance athletes.
To learn more about the type of strength exercises included amongst runners, I conducted a very non-scientific poll. Basically, it consisted of me asking my runner friends, “Hey, do you strength train? What type?” The most common answer was “Yes” and “Core.” When further probed as to how often, the most common answer was, one to two times per week. This tells me quite a bit. Strength training has indeed caught on among the endurance community, but since core work was the most popular form of strength training, this tells me most runners (in my non-scientific poll) don’t understand the relationship between strength and running.
Don’t get me wrong, I think core strength is important. Heck, any type of strength training is beneficial. Some strength is always better than none. But, to improve endurance performance the best type of strength training is maximal strength training. What?! Isn’t heavy lifting reserved for linebackers and body builders? Don’t runners do sit-ups and lift puny weights? It seems intuitive since endurance athletes don’t have (or necessarily need) really big muscles, right? Further, the nature of endurance sports incorporates long, slow, repetitive muscle contractions. It makes sense that runners should lift lighter weights with higher reps to build muscular endurance. Despite the popularity among runners, light lifting or core is not the most beneficial type of strength training. For the greatest benefits you should join the linebacker on the squat machine and try to bust out a couple reps.
The author swinging a kettlebell. All photos courtesy of Stephanie Howe.
Maximal Strength Training and Running Performance
So here’s the science lesson: endurance performance is a product of three physiologic variables: VO2MAX, lactate threshold, and economy. In fact, these three variables explain >70% of variation in endurance performance between individuals. Training can help improve VO2MAX, lactate threshold, and economy, which translates into greater fitness and improved performance. However, once aerobic capacity has been maximized, other variables, such as power, start to become increasingly important to further improve performance.
A study by Støren and colleagues (2008) investigated the influence of maximal strength training on running economy and time to exhaustion. Runners in this study completed four sets of four-repetition max of half-squats three times per week for eight weeks as a supplement to their normal training. The authors found that despite no changes in body weight or VO2MAX, the runners exhibited improved running economy and time to exhaustion (Støren et al., 2008). The results of this study suggest that strength training may improve endurance performance through improvements in neuromuscular characteristics rather than hypertrophy.
Another variable that contributes to endurance performance is running speed at VO2MAX. Although maximum speed is related to VO2MAX and economy, it also incorporates anaerobic capacity and neuromuscular characteristics. When athletes are matched for aerobic capacity (VO2MAX), anaerobic power and neuromuscular characteristics contribute to endurance performance. Thus a highly trained athlete can further improve performance by maximizing strength and power.
A recent review by Rønnestad & Mujika (2013), found that concurrent endurance and heavy strength training increases speed at VO2MAX (Vmax) or time to exhaustion at Vmax (Rønnestad & Mujika, 2013). In this review, the authors identify muscle fiber recruitment pattern as a potential mechanism for improved performance after combined strength and endurance training. Strength training increases the maximal strength of type I (slow twitch) muscle fibers delaying their time to fatigue, which in turn delays the activation of less economical type II fibers.
Another potential mechanism for improved performance is the conversion of type IIX (fast twitch) to type IIA (fatigue-resistant fast twitch) fibers. In a recent study examining a 16-week concurrent strength and endurance training on cyclists, the authors found an increase in type IIA fatigue-resistant fibers (Aagaard et al., 2011). A shift from type IIX to type IIA fibers improves endurance performance because type IIA fibers exhibit a high power output yet are more fatigue resistant than type IIX fibers. This leads to greater muscular efficiency and delayed fatigue in endurance performance.
And finally, improved musculo-tendinous stiffness has also been identified as potential mechanism for improved endurance performance in response to strength training. In running, the stretch-shortening cycle of the running stride can contribute to approximately half of the mechanical work performed during the eccentric phase. Thus, lower body musculoskeletal stiffness is associated with improved running economy. In a study by Foure and colleagues (2011), subjects participated in a 14-week plyometric training program to assess the impact on stiffness and jumping performance. The authors found an increase in joint stiffness after the training program, leading to enhanced elastic energy storage (Foure et al., 2011). In terms of endurance performance, explosive strength training increases lower body stiffness leading to improved utilization of the elastic energy and reducing the energy cost of running.
Taken together, these studies suggest that maximal or explosive strength training is most beneficial for runners. The addition of strength training to an endurance training program can further increase running economy and subsequent performance. This is especially true when all other physiological variables have been maximized through training. Despite the popularity of lower weight/high rep strength training among runners, the evidence points to greater performance benefits from maximal and explosive strength training.
Application
The challenge with results from scientific studies is actually applying them to real life. To learn more about how best to incorporate strength training, I interviewed Kyle Will, CSCS, RSCC, Head Coach of the Bend High Track & Field Team, Personal Trainer, and owner of Will Power Training Studio in Bend, Oregon. Will has years of experience working with endurance athletes of all ages from beginner up to elite. At his training studio, Will offers a ‘strength training for runners’ class designed to help improve endurance performance. Will’s class is not what you of when you hear ‘runners’ and ‘strength’ in the same sentence. Instead think explosive plyometrics and lifting weights for both the lower and upper body. Kyle also incorporates core exercises, but they are not the focus of the class.
According to Will, muscle or strength imbalance is an issue for most runners. Most have strong quadriceps and weak glutes, especially the gluteus medius. Strengthening the hip and gluteus muscles can help prevent overuse injuries, especially in the knee. Many runners don’t do strength training partly because they’d rather run if they have time for a workout. Sometimes running less and including strength training will benefit us more than fitting in the miles. Especially with age, running less and including strength training is even more important. Loss of lean muscle tissue occurs with age, and strength training is one way to help sustain a healthy body composition and prevent atrophy. Another reason runners often avoid strength training is the intimidation factor. Runners are generally weaker and aren’t always confident when lifting in a gym full of gym rats. For female runners, the stigma surrounding weight lifting is slightly different. Most females are afraid that if they lift weights they will get big or bulk up. Because of this, it’s much more difficult to get female runners to strength train.
How does strength differ between genders?
Both males and females benefit in similar ways from strength training. Historically, males tend to engage in more ‘strength-like’ activities than females. Even as young children, males tend to be more physically oriented and do more strength-based activities than females. Partly cultural norms and partly hormonal differences between genders, males tend to have more lean muscle mass than females. With that in mind, there are potentially greater benefits for females engaging in strength training than for males.
Besides a difference in overall muscle mass, females also tend to have a bigger discrepancy of quadriceps to hamstring strength. To combat this issue, Will advises focusing on hamstring strength and vastus medialis oblique (VMO) to strengthen the knee. The programming of strength specifically for women can be similar to males in terms of reps, sets, etc. The difference is that strength for women should target areas where women are anatomically different than men.
What types of exercises should a runner include?
Some of Will’s favorite strength exercises for runners include power cleans, kettle bell swings, and lifting heavy weights with low reps. Will also includes a lot of explosive exercises or plyometrics, such as box jumps. These types of exercises lead to neuromuscular adaptations within the muscles that in turn, improve running economy, and eventually performance. Many runners do lower body exercises, but do things like body weight lunges and step-ups. Although these types of exercise can help build some strength, they are not as effective as high weight/low rep or explosive exercises. Will also thinks core and upper body are important for endurance running. Core means more than just abdominal strength however. The core includes the hips to the shoulders, front to back, all the way around. Your core supports your structure and the small muscles, like the psoas or piriformis, are every bit as important as the big muscles.
Upper body is also often neglected by runners. I mean, it seems reasonable that big guns won’t really help running.
When is the best time to focus on strength?
For the best results, strength training should be included year round. Strength training should follow the same type of periodization as a normal training plan. In the off-season the focus should be on more weight and lower reps. Spend a good four months building strength during the off-season. Focus on addressing any weaknesses and lifting heavier weights. As a runner enters the pre-season, the focus should shift for more explosive body weight exercises, such as box jumps, medicine ball exercises, pushups, pull-ups, and abdominal exercises.
The author beginning a box jump.
This routine should continue through the season, with lower volume as peak races are approaching. During the bulk of the season heavy weights should be avoided, as they place a high level of stress on the body. Save the really heavy stuff for the off-season. How often? Twice a week is good, except during peak competition time. Cut back to once a week when tapering, and skip strength the week of the race. Consistency is the most important however. If you can only commit to once per week it’s more beneficial than to go a couple times a week every once in awhile. Keep in mind though that all individuals are different and strength should be incorporated based on fitness and performance. Some people will respond differently to additional strength training. Always listen to your body when changing your training. Too much of a good thing is not good.
What’s the best way to incorporate strength training?
The best way to keep up with strength training is to use a personal trainer or go to a class. It’s truly benefit to have someone guide you through a strength routine. Plus, it’s easier to stay committed if there is a social component. It’s best to get involved in some organized program. From personal experience, I can say I do better with consistent strength training when I join a group or go to a class. It’s something to keep me accountable, and I love my strength training buddies. I look forward to class each week to catch up with everyone and get my butt thoroughly kicked. :)
In summary, strength training is important—both for health and performance. The type of strength training you need depends on your goals as an athlete. For the recreational runner interested in general health and fitness, focusing on core and/or muscular endurance is sufficient. For a runner looking to enhance endurance performance, maximal strength training is most beneficial. The best way to improve strength is to be consistent with a routine. I’ve found it very helpful to train with a group or take a class; I’m less likely to do an hour of strength on my own compared to a class where I’m guided through all the exercises.
References
- Aagaard P, Anderson JL, Bennekou M, Larsson B, Olesen JL, Crameri R, Magnusson SP, Kjaer M. Effects of resistance training on endurance capacity and muscle fiber composition in young top-level cyclists. Scand J Med Sci Sports 2011;21:e298-e307.
- Barnes KR, McGuigan MR, Kilding AE. Lower Body Determinants of Running Economy in Male and Female Distance Runners. J Strength Cond Res. 2013 Oct 11. [Epub ahead of print]
- Rønnestad BR, Mujika I. Optimizing strength training for running and cycling endurance performance: A review. Scand J Med Sci Sports. 2013 Aug 5. doi: 10.1111/sms.12104. [Epub ahead of print]
- Støren Ø, Helgerud J, Støa EA, Hoff J. Maximal strength training improves running economy in distance runners. Med Sci Sports Exerc. 2008; 40(6):1087-92.
Call for Comments (from Meghan)
Do you do strength training? If so, what’s in your routine and how do you think you benefit from it?
