Do you want to become stronger, more muscular, or more explosive, and are you wondering if cardio fits in? The short answer is: yes, it can. But the way you combine strength and cardio definitely makes a difference.
What is the interference effect?
The so-called interference effect implies that endurance training (cardio) could hinder the results of strength training. For years, strength athletes believed that cardio was automatically bad for muscle growth, strength, and explosiveness. Therefore, a rule of thumb was often followed: at least six hours between strength and cardio training.
New insights
Recent research shows that this effect is smaller than previously thought. A recent meta-analysis reveals that strength and muscle growth are generally not significantly affected by cardio. Only explosive strength—such as sprinting, jumping, or Olympic weightlifting—can be negatively impacted. Therefore, for most athletes, it is perfectly possible to combine strength and endurance training, as long as sufficient attention is paid to recovery and your goals remain the central focus.
When should you pay attention?
Are you suffering from sleep deprivation, stress, or a calorie deficit? Then you recover more slowly, and combining activities can be more difficult. Even for advanced athletes who are already training at the limit in terms of strength or explosiveness, extra cardio can negatively impact performance. Do you want to peak in explosive performance, such as in powerlifting or sprint competitions? Then it is wise to limit cardio use.
Practical tips
- Priority first: if strength is your goal, start with strength training.
- Cardio after strength? Build this up slowly and pay close attention to recovery and performance.
- Time in between: if you notice negative effects, take 6 to 24 hours of rest between workouts and limit cardio to 2 to 3 times per week.
- Keep it short: avoid long endurance training; opt instead for sessions of no more than 60 minutes or short HIIT workouts of 20–30 minutes.
- Choose wisely: cycling causes less muscle damage than running and therefore requires less recovery time.
Assignment for you
Take a critical look at your current training week and ask yourself the following questions:
- On which days do I do strength training?
- On which days do I do cardio?
- How can I plan my week smartly so that both my recovery and goals are optimally supported?
- Should I adjust or combine my workouts to achieve better results?
- Can I discuss this with my trainer or coach for personal advice?
Conclusion
The interference effect turns out to be less threatening than previously thought. For most athletes, strength and cardio can be combined perfectly well without having to make significant sacrifices. Only during explosive performances is some extra caution necessary. The most important thing is to listen to your body, monitor your recovery, and tailor your training to your goals.
Do you find this difficult and could you use help with this? The personal trainers of RWIJK GYM from Rijswijk are ready to guide you in smartly combining strength and cardio, so that you get the most out of your workouts.
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