Written by Adam Tzur, founder of Sci-Fit. Scientific review by Allan Bacon, founder of Maui Athletics.
Published: March 8, 2023.
Key takeaways
1️⃣ Do cardio on rest days to speed up recovery and reduce soreness.
2️⃣ To avoid muscle loss, do cardio and strength training on different days.
3️⃣ Aim for short recovery workouts with low-intensity cardio. Avoid high-intensity training on rest days.
Can You Do Cardio on Rest Days?
We recommend that you do cardio on rest days.
It's a great way to reduce soreness and recover athletic performance.
Low-intensity exercises like light jogging, cycling, or swimming are ideal for rest day workouts.
What It Means to Take a Rest Day
A rest day is when you take a break from regular training. Your muscles get damaged during intense workouts. Afterwards, your body needs to repair and recover.
How Many Rest Days Do You Need in a Week? A Recovery Guide
Learn how many rest days you need per week. Recovery guidelines for athletes, gym goers, and beginners.
On a rest day, you can choose between two types of recovery: passive or active.
Passive recovery means you unwind, abstaining from any physical exertion. At most, you might get a massage, do cryotherapy, or stretching.
Active recovery means you do low-intensity workouts such as light cardio. It increases blood flow and promotes muscle recovery [1] [8].
Athletes have used active recovery since the 1980s to improve their performance [8].
Here is an infographic comparing passive recovery and active recovery:
You should avoid intense physical activity whether you choose active or passive recovery. For example, weightlifting or high-intensity interval training.
The Science Behind Cardio for Faster Recovery and Reduced Soreness
Doing cardio on rest days is a form of active recovery that speeds up muscle recovery.
Light exercise like jogging or swimming increases blood flow to your muscles. This clears out metabolic waste left over after intense exercise [1] [8].
The research on active recovery says:
- It can reduce muscle soreness (Delayed Onset Muscle Soreness - DOMS) [1] [2].
- It might boost athletic performance [8].
- It makes you feel more recovered, which motivates you to perform better [8].
Some studies suggest the performance benefit is small [2] [13]. Yet, one review found that 6-10 minutes of active recovery provides a performance boost [8].
We recommend adding active recovery to your rest days. A short nature walk, jog, or hike is an excellent way to recover. It will help ease muscle soreness.
Does Cardio Burn Muscle?
Cardio is often seen as crucial for losing weight and building endurance. Yet, excessive cardio can interfere with muscle growth and strength gains [4] [5].
Luckily, there are science-based strategies that prevent cardio from killing your gains.
When Cardio Prevents Muscle Growth and Strength Gains
In some circumstances, cardio can reduce muscle, power, and strength gains [4] [5] [11]:
- Timing: If you do cardio right before, during, or after strength training [5] [10] [11] [12]. The negative effect is strongest if you do cardio before strength training [7]
- Volume: If you do excessive amounts of cardio [5] [9].
- Intensity: If you do high-intensity cardio [3] [5] [9].
- Training Experience: The more trained you are, the stronger the negative effect is [10].
- Body part: Lower-body cardio reduces lower-body strength gains [11].
This is known as the “interference effect” because cardio can interfere with strength and hypertrophy.
Experts believe this happens because cardio causes fatigue that affects your performance. Additionally, research suggests cardio could block the pathway responsible for muscle growth [3] [6].
To avoid this, you want to balance strength and endurance goals. The interference effect can be mitigated if you plan cardio properly into your training program.
How to Prevent the Negative Effects of Cardio
You can prevent the negative effects of cardio if you do it on separate days from strength training. The next-best option is to separate your training sessions by at least six hours [6].
You are even safer if you do low-intensity cardio and limit it to a short duration.
For example, go for a light jog or swim for less than 20 minutes on recovery days.
None of this is to say that cardio is harmful. It has a host of health benefits. Cardio is only negative in the sense that excessive cardio can slow down muscle or strength gains.
You shouldn't worry if you are an endurance athlete.
Our advice applies to gym goers, weightlifters, and bodybuilders whose primary goal is strength and muscle gain.
It also applies to any sport where you are trying to maximize muscle mass and strength, such as American football, wrestling, or MMA. But it depends on which weight class you are trying to reach.
Still, the interference effect is small. Don’t worry about it unless you do large amounts of intense cardio right before, during, or after your strength workouts.
How to Add Cardio to Your Rest Day Workout
Your recovery workout should be light and easy. The goal is to get the blood flowing to your muscles to clear out metabolic byproducts [1] [8].
Here is an infographic showing how to plan cardio into your training program:
The Type of Cardio You Should Do
Feel free to choose whichever type of aerobic exercise you prefer. We recommend cardio that is light on joints: swimming, cycling, or running on a soft surface (i.e., nature trails). The intensity should be around 30 to 60% of your maximum heart rate.
Adding mobility training to your active recovery workout is also a good idea. Try stretching, mobility drills, and so on.
Since it’s a rest day, you should avoid intense physical activity:
- Interval training
- High-intensity exercise or sports
- Weightlifting and strength training
How Much Cardio You Should do on Rest Days
As discussed before, only 6-10 minutes of cardio gives performance benefits [8].
Do this:
- Short workouts (less than 20 minutes of cardio)
- Light cardio such as jogging, swimming, or cycling
- Maintain a low intensity
Example of a light cardio workout on a rest day
A 10-15 minute jog in the park or a ride on a stationary bike will suffice. Maintain a steady heart rate. Active recovery reduces muscle soreness and can potentially enhance athletic performance. |
References
[1] Dupuy O, Douzi W, Theurot D, Bosquet L, Dugué B. An Evidence-Based Approach for Choosing Post-exercise Recovery Techniques to Reduce Markers of Muscle Damage, Soreness, Fatigue, and Inflammation: A Systematic Review With Meta-Analysis. Frontiers in Physiology. 2018 ;9:403. DOI: 10.3389/fphys.2018.00403. PMID: 29755363; PMCID: PMC5932411.
[2] Fares, Rony; Vicente-Rodríguez, Germán; Olmedillas, Hugo. Effect of Active Recovery Protocols on the Management of Symptoms Related to Exercise-Induced Muscle Damage: A Systematic Review. Strength and Conditioning Journal 44(1):p 57-70, February 2022. DOI: 10.1519/SSC.0000000000000654
[3] Fyfe JJ, Bishop DJ, Stepto NK. Interference between concurrent resistance and endurance exercise: molecular bases and the role of individual training variables. Sports Medicine (Auckland, N.Z.). 2014 Jun;44(6):743-762. DOI: 10.1007/s40279-014-0162-1. PMID: 24728927.
[4] Lundberg TR, Feuerbacher JF, Sünkeler M, Schumann M. The Effects of Concurrent Aerobic and Strength Training on Muscle Fiber Hypertrophy: A Systematic Review and Meta-Analysis. Sports Medicine (Auckland, N.Z.). 2022 Oct;52(10):2391-2403. DOI: 10.1007/s40279-022-01688-x. PMID: 35476184; PMCID: PMC9474354.
[5] Markov A, Chaabene H, Hauser L, et al. Acute Effects of Aerobic Exercise on Muscle Strength and Power in Trained Male Individuals: A Systematic Review with Meta-analysis. Sports Medicine (Auckland, N.Z.). 2022 Jun;52(6):1385-1398. DOI: 10.1007/s40279-021-01615-6. PMID: 34878640; PMCID: PMC9124655.
[6] Methenitis S. A Brief Review on Concurrent Training: From Laboratory to the Field. Sports (Basel, Switzerland). 2018 Oct;6(4):E127. DOI: 10.3390/sports6040127. PMID: 30355976; PMCID: PMC6315763.
[7] Murlasits Z, Kneffel Z, Thalib L. The physiological effects of concurrent strength and endurance training sequence: A systematic review and meta-analysis. Journal of Sports Sciences. 2018 Jun;36(11):1212-1219. DOI: 10.1080/02640414.2017.1364405. PMID: 28783467.
[8] Ortiz RO Jr, Sinclair Elder AJ, Elder CL, Dawes JJ. A Systematic Review on the Effectiveness of Active Recovery Interventions on Athletic Performance of Professional-, Collegiate-, and Competitive-Level Adult Athletes. Journal of Strength and Conditioning Research. 2019 Aug;33(8):2275-2287. DOI: 10.1519/jsc.0000000000002589. PMID: 29742750.
[9] Panissa, Valéria Leme Gonçalves; Greco, Camila C.; Ribeiro, Natalia; Julio, Ursula F.; Tricoli, Valmor; Franchini, Emerson. Concurrent Training and the Acute Interference Effect on Strength: Reviewing the Relevant Variables. Strength and Conditioning Journal 44(3):p 46-57, June 2022. DOI: 10.1519/SSC.0000000000000668
[10] Petré H, Hemmingsson E, Rosdahl H, Psilander N. Development of Maximal Dynamic Strength During Concurrent Resistance and Endurance Training in Untrained, Moderately Trained, and Trained Individuals: A Systematic Review and Meta-analysis. Sports Medicine (Auckland, N.Z.). 2021 May;51(5):991-1010. DOI: 10.1007/s40279-021-01426-9. PMID: 33751469; PMCID: PMC8053170.
[11] Sabag A, Najafi A, Michael S, et al. The compatibility of concurrent high intensity interval training and resistance training for muscular strength and hypertrophy: a systematic review and meta-analysis. Journal of Sports Sciences. 2018 Nov;36(21):2472-2483. DOI: 10.1080/02640414.2018.1464636. PMID: 29658408.
[12] Schumann M, Feuerbacher JF, Sünkeler M, et al. Compatibility of Concurrent Aerobic and Strength Training for Skeletal Muscle Size and Function: An Updated Systematic Review and Meta-Analysis. Sports Medicine (Auckland, N.Z.). 2022 Mar;52(3):601-612. DOI: 10.1007/s40279-021-01587-7. PMID: 34757594; PMCID: PMC8891239.
[13] Querido SM, Radaelli R, Brito J, Vaz JR, Freitas SR. Analysis of Recovery Methods' Efficacy Applied up to 72 Hours Postmatch in Professional Football: A Systematic Review With Graded Recommendations. International Journal of Sports Physiology and Performance. 2022 Sep;17(9):1326-1342. DOI: 10.1123/ijspp.2022-0038. PMID: 35961644.