HEALTH & PE
Volume 6 Issue 1 2022
HEALTH & PE
Volume 5, Issue 1, 2022
Cardio or weights: what are the benefits associated with different types of exercise?
By Jackson Fyfe PhD, Postdoctoral Research Fellow, Deakin University, Melbourne
Exercise is classified into different ‘types’ that include aerobic exercise (also called ‘endurance’ or ‘cardio’) and resistance exercise (also called ‘strength’ or ‘weights’).
Different exercise types involve distinct patterns of muscle activity which, over time, produce distinct long-term changes (adaptations) such as better cardiorespiratory (heart-lung) fitness for aerobic exercise and muscle growth for resistance exercise. Despite these differences, the health-related benefits of different exercise types are relatively similar.
This article dives deeper into what makes these exercise types different, why they can promote distinct benefits, and practical ways for being more physically active.
Different ‘types’ of exercise
Broadly speaking, aerobic and resistance exercise are the two main categories.
Aerobic (also called ‘endurance’ or ‘cardio’) exercise is perhaps the most widely known, and includes activities that makes you breath more heavily, such as running, cycling, and swimming.
Resistance (also called ‘strength’) exercise sits on the opposite end of the spectrum and involves repetitions of controlled movements (exercises) performed while lifting weights or using bodyweight alone. Typical resistance exercises include lifting weights in a gym setting but other forms of exercise such as Pilates also belong to this category.
Figure 3: Resistance or strength exercises involve repetitions of controlled movements that strengthen muscles
So, what makes these exercise ‘types’ different from one another?
What makes exercise types different?
All exercise involves muscle contraction. Exercise types differ in the characteristics of the muscle contractions involved.
Compared to resistance exercise, aerobic exercise generally involves muscle contractions that produces less force but is performed more frequently (and usually over longer durations).
For example, during a 30-min run, muscles in the lower body may contract (depending on stride length and running pace) approximately 4800 times, at a rate of approximately 160 contractions per minute.
If we compare that to a typical 30-min resistance exercise session, one might perform 120 muscle contractions (assuming 3 sets of 10 repetitions were completed for 4 different exercises), at a rate of approximately 10 contractions per minute (depending on various factors).
This means that compared to resistance exercise, aerobic exercise involves lower force, but more frequent, muscle contractions and with less time (recovery) between each contraction.
So, what does this mean for the benefits associated with different exercise types?
What are the benefits of different types of exercise?
The benefits of different types of exercise are somewhat distinct – although there is a large degree of crossover in these benefits.
Performance benefits of different exercise types
At the extremes, differences in the long-term effects of aerobic exercise versus resistance exercise can be clearly seen in those who have undertaken one of these exercise types for many years, such as competitive athletes.
Endurance-type athletes, including long-distance runners or road cyclists, typically have very high levels of aerobic fitness (improved heart and lung function) and a relatively low muscle mass. This contrasts with strength-type athletes such as weightlifters, whose aerobic fitness levels are typically relatively low, but levels of muscle mass and strength are much higher.
Clearly for athletes, focusing on the type of exercise most specific to the demands of their sport is essential for maximising performance. Therefore, a long-distance runner focuses their training on running instead of cycling, and a weightlifter spends most of their training time lifting weights rather than running on a treadmill. But of course, most of us are not athletes and exercise mostly for enjoyment and health benefits.
Health benefits of different exercise types
Health-wise, aerobic exercise is typically associated with ‘cardiometabolic’ benefits, such as lower blood pressure, improved blood sugar (glucose) and lipid profile, and a reduced risk of chronic diseases such as heart disease and type 2 diabetes.
However, resistance exercise has many health benefits that are often underappreciated. It also has positive cardiometabolic benefits, with favourable effects on blood pressure, blood glucose and lipid profiles, and reduced risk of various chronic diseases including heart disease – benefits that most people associate only with aerobic exercise.
Other important benefits of resistance exercise are positive effects on muscle mass, strength, and bone density, each of which can decline across the lifespan and contribute to increased risks of falls, fractures, and a reduced ability to perform activities of daily living with aging (such as rising from a chair or climbing steps).
Both types of exercise can also have mental health benefits, with positive effects on mood, anxiety, and depression.
So, in summary – different exercise types have somewhat distinct benefits, but when it comes to improving general health, all types of exercise can have considerable benefits.
Why do different types of exercise provide distinct benefits?
The benefits of exercise are linked to the short-term stress experienced by the body during exercise.
This concept – known as ‘hormesis’ – describes how low levels of stress can have positive effects by promoting changes (known as adaptations) that improve the ability to cope with future stress.
The concept of hormesis is perhaps best captured by the phrase: “what doesn’t kill you, makes you stronger”.
So how does the type of exercise influence the type of stress placed upon the body, and how does this link to the benefits of exercise?
From a physiological perspective, the muscle activity performed during exercise determines the type of stress placed on our body systems (such as our cardiovascular and musculoskeletal systems).
The type of physiological stress placed upon a body system then determines the changes that occur in that body system over time.
For example, during aerobic exercise, because muscles contract more frequently and with less recovery between each contraction than during resistance exercise, the cardiovascular system is forced to work harder than the neuromuscular system. The opposite is true during resistance exercise, which places greater stress on our muscles and bones compared to our heart and circulatory system.
Because aerobic exercise generally involves lower force, but more frequent, muscle contractions, this places more stress on the systems within our muscles that produce the energy needed for muscle contraction. These energy systems use metabolic fuels (such as carbohydrates and fats) to generate the energy (in the form of ATP or adenosine triphosphate) needed for muscle contraction. In the process of generating ATP, these systems also produce metabolic by-products such as lactate and hydrogen ions.
When levels of metabolic fuels begin to decline, and metabolic by-products start to accumulate, the result is a type of physiological stress known as metabolic stress. With resistance exercise, muscles produce more force but contract less frequently, which together means the level of metabolic stress is lower compared with aerobic exercise, but the amount of mechanical stress is instead far greater.
The type of physiological stress experienced during exercise is therefore responsible for the specific benefits associated with different exercise types, and can explain why aerobic exercise improves cardiorespiratory fitness while resistance exercise enhances strength, muscle mass, and bone density.
Practical exercise guidelines and recommendations
Understanding the benefits of different exercise types can help us decide what kind of exercise we should incorporate into our weekly routine.
The next question, then, is how much is enough?
Current Australian physical activity and exercise guidelines suggest that for health benefits, children aged 5-17 should do at least 60 minutes of moderate-to-vigorous exercise each day (more is better), and on at least 3 days per week, perform vigorous exercise that strengthens muscle and bone.
Adults aged 18 to 64 years are suggested to be active on most (preferably all) days, and aim for 2.5 to 5 hours of moderate-intensity activity and 1.25 to 2.5 of vigorous intensity exercise (or an equivalent combination of both) per week. Adults are also encouraged to incorporate muscle-strengthening activities into their daily physical activity on at least 2 days per week.
The guidelines emphasise being active where possible during the day as well (e.g., by walking to school, helping around the house, using the stairs instead of the lift) and limiting sedentary time (sitting and lying down).
An important recent shift in exercise guidelines has been to emphasise that while specific amounts of exercise are recommended, any amount of exercise is better than none.
In support of this idea, the greatest health-related benefits of exercise occur when an individual moves from being inactive to undertaking some form of exercise. There is also evidence that even five minutes of daily exercise can reduce the risk of dying from any cause.
Whatever the type of exercise, the main factor determining the benefits of exercise is probably whether it can be performed regularly over time.
Another important – and often overlooked – factor that seems to influence physical activity levels is how exercise makes us feel.
For example, during and after exercise, one can experience feelings ranging from pleasure to displeasure (known as ‘affective valence’) in addition to various levels of arousal (such as ranging from excitement to boredom or relaxation).
Collectively these feelings are known as ‘affective responses’ to exercise.
There is some evidence that affective responses to exercise not only influence whether someone is likely to stick to an exercise program over time, but also their levels of general physical activity.
For example, research studies found that when people were asked to select an exercise intensity based on what made them ‘feel good’, and therefore find exercise more pleasurable, their levels of physical activity were higher over time compared to using a typical range-based approach to exercise prescription (e.g., exercising based on a certain heart rate range).
Another study found that ratings of affective balance during a moderate-intensity treadmill walk predicted levels of physical activity up to one year later.
So then, what are some recommendations to reap the benefits of exercise in the long-term? Because – as we covered earlier – there is lots of overlap in the benefits of different exercise types, some suggestions are to:
- Keep exercise simple and practical
- Find a type of exercise that makes you ‘feel’ good
- Focus on small amounts of exercise performed more regularly
- Find ways to be more physically active outside of structured exercise
1 .Make a table and list the following activities based on whether they would be predominantly considered to be a form of aerobic (endurance) exercise or resistance exercise: cycling, Pilates, lunges, running, high-intensity interval training, walking, skipping, push-ups.
2. Explain why the body types of athletes such as weightlifters and long-distance runners tend to be different to one another.
3. Explain why aerobic exercise leads to greater increases in aerobic fitness, while resistance exercise has greater effects on muscle mass, strength, and bone density.
4. Think about the types of exercise you enjoy most. How could you make this type of exercise as simple and as practical as possible? Come up with a plan to fit this type of exercise into your daily schedule on most days of the week (e.g., when and where will you do it?).
5. What has been identified as an important factor that determines whether people continue to sustain exercise over time? Why do you think this might be the case?
6. In small groups, discuss what you knew about different exercise types and their benefits before reading this article. Did you come across any new information about different exercise ‘types’ that surprised you?
7. What is the term used to describe the concept whereby low levels of physiological stress cause changes (adaptations) that help to cope with future stress?
8. What are the main types of physiological stress caused within our muscles during aerobic exercise and resistance exercise? Can you explain why this is the case?
9. While exercise guidelines commonly recommend a minimum amount of exercise (e.g., daily or weekly) to achieve health benefits, what did an important recent shift in these guidelines aim to emphasise?
10. In small groups, brainstorm at least five examples of where someone could be more physically active (other than structured exercise) during the day.
References and further reading
Australian physical activity guidelines: https://www.health.gov.au/health-topics/physical-activity-and-exercise/physical-activity-and-exercise-guidelines-for-all-australians
BetterHealth channel: Benefits of resistance training: https://www.betterhealth.vic.gov.au/health/healthyliving/resistance-training-health-benefits
A closer look at the adaptations to different exercise ‘types’ and why these occur:
- Aerobic exercise: https://www.gssiweb.org/en-ca/article/sse-54-muscle-adaptations-to-aerobic-training
- Resistance exercise: https://www.sportsci.org/encyc/adaptex/adaptex.html
‘Exercise Right’ resources: https://exerciseright.com.au/
BetterHealth channel: How to get started with physical activity: https://www.betterhealth.vic.gov.au/health/healthyliving/physical-activity-how-to-get-started
Baldwin, A. S., Kangas, J. L., Denman, D. C., Smits, J. A. J., Yamada, T., & Otto, M. W. (2016). Cardiorespiratory fitness moderates the effect of an affect‐guided physical activity