The great cardio versus weight training debate has raged on for decades and still continues today. But what, exactly, is better for weight loss?
Among women especially, there is a commonly held belief that cardio is best to lose weight, while weight training is often sidelined as many feel that it will make them ‘big and bulky’.
While spending an hour on the cardio machines at the gym can fail to realise your weight-loss and body transformation goals, boiling the debate down to one exercise modality over another oversimplifies a complex topic.
There are many interrelated factors to consider. For instance, a poor diet will make it difficult to lose weight with either training approach. As the popular saying states, “you can’t out-train a bad diet”, and low to moderate steady-state cardio for an hour or less each day does little to burn significant calories.
Furthermore, walking, running or pedalling at the same intensity and duration over prolonged periods will also become less effective over time as the body adapts.
And cardio definitely doesn’t build muscle. This is an important consideration in the weight-loss equation because metabolically active muscle tissue will boost your metabolism.
As such, you’ve likely heard that a weight training-based approach is best to boost your metabolism, especially high-intensity interval training (HIIT). Intense exercise against resistance also has a more pronounced metabolic effect, which helps to burn additional calories, even after your workout.
But this debate doesn’t need to have an either-or answer. A leading local sports scientist argues that high-intensity in either form can deliver weight-loss results.
“Weight loss needs energy consumption. One can quibble about energy in versus energy out and the semantics and loopholes in this, but the bottom line, from a physics point of view, is that if you are losing weight, it’s because your energy output is greater than your energy intake,” explains Dr Ross Tucker.
The nuances regarding which nutrients your body burns versus those it stores are irrelevant to the ultimate outcome of this equation. However, they do affect how it plays out in the process.
“And cardio,” Dr Tucker says, “means more energy consumption.”
However, that’s not to say weights don’t help, he adds. “To say it’s either A or B creates a false dichotomy between the two. Weight training also burns calories, and it also assists with weight loss, but per unit time (60 minutes, for example), cardio involves more. The benefit of weight training is increased lean mass, which helps with maintenance, and delivers other benefits like strength and injury prevention.”
As such, he suggests that a combination is always the best because “the world should not be reduced to simplistic outcomes that exist in isolation.”
Available research affirms this stance, including analysed data related to strength training and cardiovascular exercise collected during the landmark Women’s Health Study (WHS).
The research team found that women who engaged in strength training were more likely to have a lower body mass index (BMI), were more likely to eat healthfully, and were less likely to smoke compared with women who did not train with weights.
As a result, participation in any strength training was associated with a 30% reduction in type 2 diabetes, which has significant weight-related implications, among other health benefits.
However, those who engaged in both strength training and aerobic activity experienced the greatest reduction in type 2 diabetes (and cardiovascular disease) risk compared with either aerobic activity alone or no training, according to the study findings.
Compared with women who did no form of exercise, those who participated in both strength training and did 120 minutes or more of aerobic activity experienced a 65% reduction in type 2 diabetes risk. Women who skipped the gym and did only 120 minutes or more of aerobic activity experienced a 48% reduction.
According to researchers, weight training increases muscle mass and reduces BMI, which potentially leads to greater insulin sensitivity and more efficient glucose transport and metabolism, which accounts for the observed benefits (these have weight loss and health implications).
Although endurance training also improves glucose metabolism, the larger gains in muscle tissue from strength training may explain the greater risk reduction for type 2 diabetes (and cardiovascular disease) compared to those who only engaged in aerobic exercise.
A combined approach
With these factors in mind, combining weight training – ideally HIIT – with 120 minutes or more of cardiovascular exercise a week is potentially the most effective approach to follow for weight loss.
When training with weights, focus on movements that incorporate bigger muscles groups – stick mainly to the major compound exercises such as squats, deadlifts, push-ups, pull-ups, and presses.
You can intersperse sets or exercises with bursts of intense cardio intervals if you don’t want to structure every workout with separate cardio and weight training sessions. It is beneficial to use varied pace and intensity during the cardio component of your session, rather than just steady effort.
Then, aim to get out for a longer cardio session performed in a fasted state (before breakfast) at least once a week – over weekends is an ideal time. Aim to remain active at a moderate to high intensity for 90-120 minutes.
Drink only water during the session and have your first meal of the day when you are done. Exercising in this state is an effective way to boost fat metabolism to aid weight loss and conditioning.