Why Cardio Matters: Unlocking the Benefits of Aerobic Activity for Everyone

When we think of cardiovascular (cardio) exercise, we often imagine activities like running, cycling, or swimming that get our heart pumping and make us sweat. The primary belief is that cardio is crucial for maintaining a healthy heart and lungs, improving endurance, and burning calories for weight management. These reasons form the foundation of why many health professionals emphasize the importance of aerobic activity in a well-rounded fitness regimen.

The World Health Organization (WHO) and other health authorities such as the American Heart Association (AHA) recommend that adults engage in at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic physical activity per week. This can be broken down into sessions of at least 10 minutes each. The rationale behind these recommendations is to reduce the risk of chronic diseases such as heart disease, stroke, type 2 diabetes, and others. Additionally, regular aerobic exercise is linked to improved mental health, better sleep quality, and enhanced overall quality of life.

Is That Supported By Current Research?

The benefits of cardiovascular exercise are well-documented. A 2022 randomized controlled trial expressed that, for participants engaged in high, moderate or low intensity, “general health scores increased […], vitality and social functioning scores […] increased moderately [and…] tiredness, back pain, and physical stamina scores […] showed moderate to strong changes.” (PMID35209911). A 2023 meta-analysis of randomized controlled trials talks about the effects of aerobic activity on blood pressure: “aerobic exercise can lead to a large and clinically important reduction in blood pressure in a dose-dependent manner, with the greatest reduction at 150 min/week.” (PMID37872373) Following my recent blog, body composition is very important for health. A 2017 randomized controlled trial talks to the importance of aerobic activity in regulating and aiding said body composition. Its results state that “high-intensity exercise intervention with high energy expenditure can considerably reduce body weight, body fat, WC, WHR, and WHtR, […] a light-intensity exercise intervention can significantly reduce body weight and body fat.” (PMID28836987).

However, recent research has nuanced our understanding of its role in recovery. Some studies suggest that cardio may not be as effective for recovery as previously thought, especially for athletes engaged in high-intensity training. A 2021 randomized controlled trial showed that aerobic training did not significantly alter cardiovascular reactivity or recovery from challenges in healthy young adults (PMID21257979). This follows a previous trial in 2013 which also found no significant differences between aerobic and strength training in terms of their effects on cardiovascular sympathetic responses and recovery (PMID23889039). These shed light on the complex relationship between cardiovascular exercise and its effects on the body's response to stress and recovery. While aerobic exercise is widely known for its heart health benefits, these studies suggest that it might not significantly change how our bodies react to or recover from stressful challenges. The findings suggest that the cardio-protective effects of regular aerobic activity might not be due to changes in these acute cardiovascular responses or responses to the immediate reactions of the cardiovascular system to stressors or physical challenges, including changes in heart rate, blood pressure, and how the heart and blood vessels respond to sudden physical or psychological stress. These responses are important because they help our bodies cope with short-term demands and return to a resting state efficiently. Instead, the benefits of aerobic exercise may lie in other areas, such as improved metabolic health, enhanced overall fitness, and reduced inflammation. Therefore, understanding these nuances is crucial as they encourage a broader exploration of how cardiovascular exercise supports long-term heart health and overall well-being.

Cardio for All

For the general population, we have to asses what it is that we are trying to achieve with cardio. As the trainee yourself you may be or the trainer you are, how do you include cardio into your weekly routine without any interference affect? I believe that for the general population, the primary goals of cardio are:

1. Heart Health: regular aerobic activity strengthens the heart muscle, improves circulation, and lowers blood pressure, reducing the risk of heart disease.

2. Body Recomposition: cardio can contribute to weight/fat loss or maintenance when combined with well-established nutritional practices.

3. Mental Health: engaging in any type of physical activity can improve mental health, increased life satisfaction in adolescents (PMID37611913) and significantly reduce depressive symptoms (PMID35007642).

4. Life Activities: improved movement and endurance makes everyday tasks easier, from climbing stairs to playing with children.

Here is how I incorporate cardio in my program tailored to the non-sport-specific population, Kaizen Everfit:

• Start Slow: begin with manageable activities like low-impact, brisk walking, or light jogging. The effects of cardio on health do not seem to vary based on intensity but by volume. Starting or even progressing in intensity is unnecessary if it interferes with other daily tasks. Ideally, we progress to accumulating 150 minutes per week of said activity.

• Mix It Up/Be Flexible: incorporate different types of cardio, such as swimming, cycling, or dancing, to keep things interesting and in turn keep you consistent. There is no said intensity or type of activity that seems to be better for your health. As long as you are active for the goal of 150min per week, choose any activity or cardio type that is going to keep you consistent.

• Consistency Over Intensity: aim for regular, low to moderate-intensity sessions rather than sporadic high-intensity workouts. Not only is there no difference in your health, but the ladder will make it easier for you to go about life after the session. Assuming you have other responsibilities throughout the day, you do not want to die in a high-intensity training session, be sore for days, and not be able to do what you like or need to do.

• Warm Ups: add 10min of low intensity cardiovascular work as your warm up to accumulate at last 20-30min of the 150 minutes of weekly aerobic activity. We know that elevating heart rate is one essential part of a warm up so get started doing this.

• Track Progress: using a fitness tracker, health device or app can help you monitor your activity and stay motivated. If you feel comfortable doing so, tracking things like resting heart rate, daily steps or daily expenditure can help you track how you are doing. Again, fitness devices may not be accurate, but if you do it consistently, they might turn very precise and help you.

Conditioning for Athletes

For athletes, conditioning might play a different yet equally important role. While strength, power, and sport-specific skills are critical, aerobic fitness can significantly enhance the timespan an athlete can demonstrate all of those other qualities. When programming aerobic protocols, we have to understand what we are trying to achieve with those:

1. Physical Endurance: the ability for athletes to demonstrate their skills and physical qualities at a high level and output for a longer period of time. A 2017 randomized controlled trial shows us that incorporating varied, high-intensity activities into sport-specific conditioning can enhance overall fitness and athletic performance more effectively than sport-specific drills alone (PMID27140481).

2. Mental Endurance: a 2020 randomized controlled trial concluded that mental fatigue significantly impairs physical activity, technical skills, and decision-making performance in soccer players (PMID33789683). Enhanced physical endurance allows the athlete to think more clearly for longer. When fatigue and oxygen deficit start setting in, you might feel like your or your athletes’ ability to make decisions starts decreasing.

Considerations When Including Conditioning For Your Athletes:

• Prioritize Sports Practice & Performance: when adding conditioning to your program, we have to make sure the total added stress does not exceed an athlete’s abilities and capacity. Athletes will and should get much of their conditioning through sports practice. Once that settles and the athlete develops good restorative and recovery-inducing habits, then we can start implementing more activity and stress.

• Tailor to Your Sport: choose cardio activities that complement your sport. While many grounded sports should be able to run for long because that is what they do, that might not be suitable right now for that athlete. Again, to comes down to capacity vs stress. You might think of building up slowly while maintaining good caloric balance and recovery. You might also think of different activities that complement your sport. Best example is an air bike for swimming, and learning how to coordinate upper and lower body to create as high of an output as you can.

• Interval Training: a 2007 randomized controlled trial concluded that high-intensity aerobic interval training has been shown to significantly improve VO2max, compared to moderate training methods such as long slow distance and lactate-threshold training. This increase in VO2max is important because it enhances cardiovascular fitness and overall endurance, allowing individuals to perform physical activities more efficiently and with greater stamina (PMID17414804).

• Listen to Your Body: adjust cardio intensity and duration based on the prioritized training load (sports specific practice, strength, speed and agility work) and recovery needs to avoid burnout and overtraining.

Conclusion

Cardiovascular exercise remains a cornerstone of a healthy lifestyle, offering numerous benefits for heart health, longevity, and overall well-being. By understanding the latest research and incorporating cardio thoughtfully into your fitness routine, both the general population and athletes can maximize its benefits while supporting performance goals. Whether you're aiming for better health or peak athletic performance, finding the right balance of aerobic activity can help you achieve a healthier, more active life.

1. Berge J, Hjelmesæth J, Kolotkin RL, Støren Ø, Bratland-Sanda S, Hertel JK, Gjevestad E, Småstuen MC, Helgerud J, Bernklev T. Effect of aerobic exercise intensity on health-related quality of life in severe obesity: a randomized controlled trial. Health Qual Life Outcomes. 2022 Feb 24;20(1):34. doi: 10.1186/s12955-022-01940-y. PMID: 35209911; PMCID: PMC8876087.

2. Jabbarzadeh Ganjeh B, Zeraattalab-Motlagh S, Jayedi A, Daneshvar M, Gohari Z, Norouziasl R, Ghaemi S, Selk-Ghaffari M, Moghadam N, Kordi R, Shab-Bidar S. Effects of aerobic exercise on blood pressure in patients with hypertension: a systematic review and dose-response meta-analysis of randomized trials. Hypertens Res. 2024 Feb;47(2):385-398. doi: 10.1038/s41440-023-01467-9. Epub 2023 Oct 23. PMID: 37872373.

3. Chiu CH, Ko MC, Wu LS, Yeh DP, Kan NW, Lee PF, Hsieh JW, Tseng CY, Ho CC. Benefits of different intensity of aerobic exercise in modulating body composition among obese young adults: a pilot randomized controlled trial. Health Qual Life Outcomes. 2017 Aug 24;15(1):168. doi: 10.1186/s12955-017-0743-4. PMID: 28836987; PMCID: PMC5571495.

4. Ahmed KR, Horwood S, Khan A. Effects of a School-Based Physical Activity Intervention on Adolescents' Mental Health: A Cluster Randomized Controlled Trial. J Phys Act Health. 2023 Aug 22;20(12):1102-1108. doi: 10.1123/jpah.2023-0062. PMID: 37611913.

5. Philippot A, Dubois V, Lambrechts K, Grogna D, Robert A, Jonckheer U, Chakib W, Beine A, Bleyenheuft Y, De Volder AG. Impact of physical exercise on depression and anxiety in adolescent inpatients: A randomized controlled trial. J Affect Disord. 2022 Mar 15;301:145-153. doi: 10.1016/j.jad.2022.01.011. Epub 2022 Jan 7. PMID: 35007642.

6. Fernandez-Fernandez J, Sanz D, Sarabia JM, Moya M. The Effects of Sport-Specific Drills Training or High-Intensity Interval Training in Young Tennis Players. Int J Sports Physiol Perform. 2017 Jan;12(1):90-98. doi: 10.1123/ijspp.2015-0684. Epub 2016 Aug 24. PMID: 27140481.

7. Trecroci A, Boccolini G, Duca M, Formenti D, Alberti G. Mental fatigue impairs physical activity, technical and decision-making performance during small-sided games. PLoS One. 2020 Sep 9;15(9):e0238461. doi: 10.1371/journal.pone.0238461. PMID: 32903263; PMCID: PMC7480836.

8. Helgerud J, Høydal K, Wang E, Karlsen T, Berg P, Bjerkaas M, Simonsen T, Helgesen C, Hjorth N, Bach R, Hoff J. Aerobic high-intensity intervals improve VO2max more than moderate training. Med Sci Sports Exerc. 2007 Apr;39(4):665-71. doi: 10.1249/mss.0b013e3180304570. PMID: 17414804.

9. Sloan RP, Shapiro PA, DeMeersman RE, Bagiella E, Brondolo EN, McKinley PS, Crowley O, Zhao Y, Schwartz JE, Myers MM. Impact of aerobic training on cardiovascular reactivity to and recovery from challenge. Psychosom Med. 2011 Feb-Mar;73(2):134-41. doi: 10.1097/PSY.0b013e31820a1174. Epub 2011 Jan 21. PMID: 21257979; PMCID: PMC3350788.

10. Lindgren M, Alex C, Shapiro PA, McKinley PS, Brondolo EN, Myers MM, Choi CJ, Lopez-Pintado S, Sloan RP. Effects of aerobic conditioning on cardiovascular sympathetic response to and recovery from challenge. Psychophysiology. 2013 Oct;50(10):963-73. doi: 10.1111/psyp.12078. Epub 2013 Jul 28. PMID: 23889039; PMCID: PMC3815518.