Cutting-edge research provides a new perspective into the weights before or after cardio question and the answer is likely not what you thought.
Let’s make a few basic assumptions. You are a cyclist, but not a pro (a pro cyclist, that is). You are a competitive amateur or recreational cyclist who strives to maximize your potential through hard work, perseverance, and a sensible training plan.
You’ve done the research, some of which you found after jumping into the rabbit hole and landing on this blog’s Training & Performance page, and acknowledge the performance-enhancing merits of strength training. You have committed to including resistance exercise in your training and will follow a periodized approach, like the plan outlined in this article previously posted on The ZOM.
Now, this is the big one. The time demands of being a pro at something other than cycling and caring for your loved ones place a significant constraint on available training time. You have to perform your cycling and weight training in the same workout concurrently.
What should you do first? Recent scientific advancements in the study of the molecular impacts of exercise sequencing shed light on the question. But first, a bit of history.
The History of the “Interference Effect” Theory
Robert Hickson was a scientist at the University of Illinois at Chicago and also happened to be a dedicated powerlifter. The birth of his hypothesis dates back to the 1970s when he decided he wanted to improve his fitness and joined his colleague, professor John Holloszy (considered the father of endurance exercise research), during his daily afternoon run.
Despite continuing to follow his regular strength training program, Hickson was getting weaker and losing muscle mass. Robert was intrigued and initiated an experiment to explore the reasons why.
The 1980 study examined three groups of subjects. The first group only lifted weights, and the second group followed a combination of endurance activities – cycling, and running. The individuals in the third group combined endurance and resistance training.
As anticipated, the leg strength of the subjects in the strength-only group consistently improved throughout the 10-week training program. The leg strength of the individuals in the combined group leveled off after seven weeks of training and then decreased.
The cycling VO2 max increased 25% in both the endurance and combined groups, whereas the leg strength of the endurance group did not improve. As detailed in this article previously posted on The ZOM, the beneficial impact of resistance training on cycling performance is significant.
However, Hickson concluded that concurrently training for strength and endurance results in a reduced capacity to gain strength (with no effect on the ability to increase VO2 max). Hickson termed his discovery the “Interference Effect,” and it became the go-to answer to the concurrent training question.
Athletes, coaches, and sports scientists have been finding new ways to answer this question ever since. In fact, here is your coach now.
In an Ideal World, the Answer is the Priority
It is your coach speaking, and I would like you to eliminate the potential for interference by doing your weights and cycling on different days. I’d also like you to leave ample time to recover following each workout.
In an ideal world, or if you were a pro (a pro cyclist, that is), the answer would be clear. We have made the assumption, and life says this is not an option. You must do both concurrently.
Despite this, the answer is still an easy one for you. Pick the one that is a priority. Resistance training first if strength improvement and muscle mass development is your goal. Cycling first if improvements in endurance and performance are your focus.
Going into each training session fresh and using that untapped energy for what you consider of greater importance is logical. Perhaps you can’t decide what’s more important. Or, you want to know if there is a benefit to performing one before the other. A recent study sheds light on this question at the molecular level.
The Molecular Impacts of Concurrent Training
Alterations in systemic factors following cycling caused a beneficial increase in the expression of genes and proteins involved in the adaptation of muscles that makes them stronger. The new study, published in Scientific Reports, gives a molecular explanation for the beneficial effects of endurance before strength training.
In the study, the subjects performed 20-minutes of intense cycling before performing an upper-body resistance training workout. During a separate session, the group worked out but did not get on the bike first.
During each session, the researchers drew blood and took muscle biopsies from the triceps before and at several intervals after the upper-body workout. The scientists microscopically examined the blood and biopsies, searching for systemic factors indicating changes in muscular responses to exercise. What they found was extremely interesting.
Cycling Training Creates a Full Body Strength Effect
The samples taken following cycling showed an increase in proteins and markers of gene activity when compared to the strengthening-only group. In addition, the scientists detected proteins and gene activity associated with endurance improvement also.
Training concurrent endurance before resistance better prepared the subject’s muscles on a molecular level to improve in strength, size, and stamina. The endurance training intensified the potential weight training benefits without any interference.
Most significant, perhaps, is that the authors found the molecular changes created by exercise involving the legs in the muscles of the arms. The biomechanical factors produced following leg endurance exercise were distributed through the bloodstream to facilitate molecular processes in unrelated muscle groups. Endurance training with the legs activated molecular pathways in the arms.
This is Only One Short-Term Study
Feather your brakes. This recent research is of a small sample taken over a short period. It’s a different way to look at the concurrent training question but not a definitive answer. It does, however, open your eyes to the notion that there are other factors at play.
It’s not simply a matter of priority, fatigue, or other physical factors, but unseen changes are happening at the molecular level that has an influence. If you are left feeling betrayed without a solid answer to the concurrent training quandary, I leave you with this.
Conclusion - An Answer?
Since the landmark study performed by Robert Hickson in 1980, the topic has been explored extensively without a consensus. The majority of the evidence I have researched points to strengthening before endurance as the answer, however.
Sequencing strength before endurance produces favorable lower body strength adaptations without affecting aerobic capacity as described in this study (Murlasits et al. 2017). Well-trained cyclists riding for two hours at 65% maximal aerobic power reduced muscular peak torque by 14%, an outcome the researchers attributed to a fatigue-related decrease in nerve stimulus to the muscles in this study (Lepers, R et al. 2000). The aforementioned are a small sample of various studies endorsing strength before endurance, like this one (Eddens et al. 2018) as well.
However, studies to the contrary muddy the waters and make the decision more challenging. Subjects showed increased aerobic capacity and strength in a group that performed aerobic then resistance exercise compared to resistance exercise alone in this research (Lundberg et al. 2013). But not as many, to my knowledge.
The fact remains that training different modalities on different days to avoid interference is oversimplistic and not realistic for the amateur athlete. It is also clear that even though there is only one concurrent training question, there are many answers. The answers involve multiple body systems, levels of complexity, and cause-effect relationships.
Now that you know the factors involved, make the proper choice for you. Despite the sequence you choose, incorporating resistance training into your cycling training plan is a good idea. You will be happy you did.
When forced to work out and ride the same day, what do you do first and why? Comment below! Your fellow virtual cyclists want to know.
For more great articles and research into the cycling performance benefits of resistance training check out the Training & Performance page on The ZOM.
Semi-retired as owner and director of his private Orthopedic Physical Therapy practice after over 20 years, Chris is blessed with the freedom to pursue his passion for virtual cycling and writing. On a continual quest to give back to his bike for all the rewarding experiences and relationships it has provided him, he created a non-profit. Chris is committed to helping others with his bike through its work and the pages of his site.
In the summer of 2022, he rode 3,900 miles from San Francisco to New York to support the charity he founded, TheDIRTDadFund. His “Gain Cave” resides on the North Fork of Long Island, where he lives with his beautiful wife and is proud of his two independent children.
You will read him promoting his passion on the pages of Cycling Weekly, Cycling News, road.cc, Zwift Insider, Endurance.biz, and Bicycling. Chris is co-host of The Virtual Velo Podcast, too!