Endurance is often thought of as the enemy of strength. Meanwhile, building muscle and strength are assumed to cause detriment to endurance performance.
Training for strength and endurance at the same time is a delicate balance, but doing it properly will improve your athletic performance and give you a physique to be proud of.
Yeah, we’ve written a lot about the importance of prioritizing anaerobic exercise if your goal is fat loss. And if you just want to get as strong as possible or be totally shredded, heavy lifting and sprints are the best way to get there.
But the reality is that a lot of people just want to be moderately strong, sexy lean, and have the ability to get into a pick up game or play tag with their kids without embarrassing themselves. In fact, many people prefer training for endurance goals rather than for strength.
The difficulty with training for strength and endurance simultaneously is that there’s a well documented “interference” phenomenon in which people who lift weights and do endurance exercise simply don’t see the strength or muscle gains they’d expect.
Sports scientists have been looking for ways to get better concurrent training results. Here are a few conclusions they came to in a recent review of what happens when people train for strength and endurance at the same time:
• Concurrent training doesn’t compromise endurance performance—rather, it tends to improve speed and work capacity—but it blunts the development of muscle, strength, and power.
• A high-intensity of concurrent training (heavy loads and sprint intervals) is most effective for reducing body fat in both endurance and strength athletes. Sprints increase activity of an enzyme that enhances the rate of fat burning.
• Sprint-endurance training doesn’t lead to a decrease in muscle mass but they do increase metabolic rate after exercise to a degree that corresponds with the intensity of the training.
• Muscle mass is compromised when endurance training is performed more than three times a week for more than 20 minutes. In the short-term hypertrophy is blunted. In the long-term, muscle is lost if strength training is not performed or if nutrition is poor.
• Concurrent training leads to a very significant decrease in power output that corresponds to the length of the endurance exercise.
• Power is the performance variable that is compromised the MOST by endurance exercise—much more than strength or hypertrophy are.
• Women recover faster than men (one study found maximal strength was recovered within 4 hours in women and it took 48 in men!). However, the majority of concurrent training studies have been done on men, indicating that much is still unknown about the optimal concurrent training guidelines for females.
Despite the suboptimal strength and power results that come with concurrent training programs, there are strategies you can use to maximize the benefits. This article will look at three concurrent training models to guide your pursuit of the best body and optimal performance.
#1: The Elite Athlete: Get Strong, Reduce Body Fat & Get Faster
A series of studies on elite endurance athletes show that performing heavy load strength training can improve performance by reducing body fat and building type II muscle fiber strength. The result is greater speed and the ability to sustain higher work rates with more efficient oxygen use.
For example, a study of elite Danish national team cyclists showed that doing a lower body strength training program with loads ranging form 70 to 90 percent of the 1RM resulted in the following outcomes compared to a control group of cyclists:
• The concurrent group lost 2 percent body fat, increased quadriceps strength by 12 percent and improved peak 45 minute time trial performance by 8 percent.
• The control group lost 0.5 percent body fat and had no increase in strength or change in performance.
• The concurrent group gained 2 kg in lean mass, but ended with the same body weight as at baseline due to the loss of body fat. They increased type IIA muscle fibers distribution in the quadriceps from 26 to 35 percent and decreased type IIX fibers from 5 to 0.6 percent, a favorable shift for endurance performance.
Researchers suggest that the endurance component of concurrent training provides an “atrophy” stimulus that blunts the muscle growth response in the muscles that are engaged in endurance exercise. Muscle growth is not inhibited in muscles that aren’t performing repetitive training.
Therefore, if you’re an endurance runner or cyclist, you should be able to gain more muscle in the upper than the lower body if you do upper body lifting. A swimmer or rower might not see such growth.
Regardless, strength training is beneficial in all endurance competitors because it builds neuromuscular strength and greater motor unit recruitment.
How To Do It:
If the goal is endurance performance, do heavy load strength training in the body parts that are engaged in endurance exercise to improve strength, speed, and work economy. Muscle building will be blunted but body fat can be reduced for superior body composition.
To build muscle for aesthetics, you’ll pack on significant muscle if you do a lifting program for the part of the body that is not engaged in endurance exercise. In addition, do a large portion of your endurance workouts as intervals and favor intensity over duration for a more anaerobic stimulus.
Focus on recovery by training diverse modes on separate days and get adequate nutrition. Researchers point out that recovery is largely under our control, requiring protein for sustained muscle repair, carbohydrates to replenish glycogen, and micronutrients such as magnesium, zinc, vitamin C, and sodium for oxidative stress and cortisol management.
#2: The Endurance Competitor: Lift Heavy To Improve Work Economy & Speed
A common error for endurance competitors is to ignore the importance of strength and power for performance. Endurance athletes often do muscular endurance resistance training programs with light loads and high reps, which has little to no benefit on performance.
Instead, heavy load training for light reps will increase muscle work efficiency so that athletes can sustain faster speeds for longer. For example, s study performed on Spanish national team runners, found that a Strength Group that did 3 sets of 7 using a load of 70 percent of the 1RM followed by a plyometric exercise had an increase in maximal oxygen uptake (VO2 max), running economy, peak velocity, and time trial performance in a 3 km trial.
Also noteworthy, trainees had lower RPE scores and performance improvements were maintained during a 5 week detraining period when no weight training was performed.
Researchers conclude that maximal strength produces a superior work economy by reducing the degree of type II muscle fiber exhaustion. Lactate threshold is increased and neuromuscular coordination is enhanced.
How To Do It:
Training errors lead to reductions in motor unit recruitment and unfavorable fiber type transformations. Avoid this by using shorter training phases (called block training) of 3 to 5 weeks. Perform highly concentrated training loads of greater than 50 percent of the regular training volume. Then use reduced volume and intensity to allow for optimal recovery and adaptation.
Depending on your competitive schedule, you don’t necessarily have to lift year round. You might get more payoff for your efforts if you give it your all in lifting workouts for block periodized cycles and then take a month off or reduce the frequency of training.
Train to develop only two target fitness components—one for endurance and one for strength. For example, a phase one might have more than 55 percent of endurance training at moderate intensities with a muscle building (hypertrophy) lifting program.
Phase two might spend as much as 45 percent of the endurance training in the high-intensity zone with the lifting program focused on maximum strength.
If the goal is an endurance competition, perform three or fewer lifts per week. If the goal is strength, four lifts and three or fewer short (less than 30 minutes) steady-state endurance workouts is generally indicated. Additional interval workouts can be used.
#3: The All-Purpose Athlete: Power, Endurance & Muscle
CrossFit provides a unique model for training for strength and endurance at the same time. Although, the all-purpose athlete may require distinct skills from a CrossFitter, a recent study by the Human Performance Lab at Arkansas State University provides data for us to consider the best methods for getting powerful, strong, and aerobically fit all at once.
Researchers recruited two groups of young recreational athletes that included both men and women: One of CrossFitters and one of traditional strength trainees. Then they had them do a 1.5 mile run, two anaerobic step tests for power, and body composition assessments.
Results showed that the CrossFitters had significantly greater average power in the step test and the difference was most pronounced in the men. Endurance performance in the 1.5 mile run was much faster in the female CrossFitters than the traditional strength trainees. In males 1.5-mile time was nearly equal.
Body fat in the male CrossFitters was 13 percent compared to 10 percent in the traditional strength trainees, and 18 percent in the female CrossFitters compared to 17 percent in the traditional trainees.
Researchers were surprised to find that CrossFit training led to greater power ability, particularly because endurance capacity was also high, and the two do not go together. Remember that power is the performance variable that is compromised the most by endurance exercise.
Maximal strength in the CrossFitters did not correlate with power or endurance performance, indicating that programming variables could be improved to yield better all-around results (such as a higher 1RM deadlift).
How To Do It:
For CrossFit, make sure you are doing a periodized program that trains your weaknesses and focuses on technique. Opt for an “intensity approach” that favors training for speed and strength over marathon-like repetition.
CrossFit coach Jeff Serven describes this distinction: “There is no number of 135 power cleans that will equal one at 315 pounds.” You’ll still be getting endurance training out of it, but you’ll be powerful, fast, and strong.
As a general rule, scientists believe that strength training to failure is not necessary for performance gains. However, it can produce superior results in more advanced athletes when done for a short training phase with moderate volume and adequate rest.
Strength training to failure and endurance workouts should be done on separate days, with recovery maximized.
When not training to failure but doing two workouts a day, try to get 6 to 8 hours between workouts and focus on refueling and recovery. A guideline that is most applicable to recreational competitors is to train the most challenging mode according to your chronobiology.
For example, if you like to do endurance training and you are a “morning” person, lift in the morning (the harder training mode) and do the endurance workout later when you are less motivated. Flip it around if you are an “evening” person and feel most motivated then. Naturally, you can mix it up based on primary goals and scheduling needs.
Be aware that under-recovery may the primary impediment to results with concurrent training. This doesn’t just mean time between workouts, but is influenced by factors such as the following:
1) low muscle glycogen that impairs intracellular signaling response to lifting,
2) muscle degradation due to low blood amino acid levels, and
3) the type of muscle action (eccentric, concentric, and isometric) such that sports that emphasize eccentric muscle lengths like running shouldn’t be paired with eccentric-enhanced lifting without adequate recovery (on the same day for example).