Aerobic Training vs. Resistance Training, Which is Better?

Throughout the history of modern fitness, there has always been a partition between what we call aerobic/cardio training enthusiasts and resistance training proponents. Both teams manage to find a scientific basis to support their claim that their training of choice is superior to the other. While both types of training have extensive scientific merit when it comes to the scientific literature, the caveat with this debate is that the advantages of both types of training lie on the extreme opposites of the fitness spectrum, and making it harder to reconcile these differences of opinion. In this review, we will briefly discuss the health and fitness benefits of both types of training and explore the emerging scientific data and studies about a hybrid training that combines both aerobic and resistance training.

Aerobic training advocates usually ascertain that if you want to lose weight, cardiovascular training is the way, and they are not completely wrong. Many studies prove this fact. Geliebter et al. 1997, for example, showed that a group undergoing aerobic training coupled with a caloric restriction for 8 weeks lost a significant percentage of their initial starting weight. Additionally, the fat mass loss in this group was also significant compared to the initial fat mass the participants had [1]. However, the same study showed that the group that was doing the resistance training regimen lost almost the same amount of weight concomitant with fat-free mass preservation (FFM) and a significant increase in their arm and grip strength compared to the aerobic training group [1]. In 2019, a meta-analysis by Hsu et al. studied the effects of exercise (whether aerobic or resistance training) and nutrition on body composition, general health, and physical performance in adults with sarcopenic obesity (people having low muscle mass and high-fat percentages). This meta-analysis showed that aerobic exercise significantly decreased body weight; however, resistance exercise showed a more significant decrease in body fat percentage compared to aerobic exercise. Additionally, grip strength increased only in the resistance exercise group. Interestingly, a combined regimen of both aerobic and resistance exercise also leads to a significant decrease in body fat percentage and a significant increase in walking speed [2]. Moreover, two randomized controlled trials (RCTs) by Lee et al. studied the effect of aerobic and resistance exercises in adolescent obese males and females on body weight composition. Significant reductions in percent body fat and waist circumference were observed in both genders upon both aerobic and resistance training. Only males showed an increase in muscle mass due to resistance training alone. Females showed no difference in their muscle mass [3, 4]. This might be attributed to the genetic and hormonal differences between both genders or due to key different methodologies done during these studies [5]. More about this here and here.

The benefits of exercise do not only improve physical health and body composition in obese people, but also many studies elucidate the effects of exercise on people with different illnesses. One Randomized controlled trial (RCT) in 2019 studied the effect of high-intensity interval training (HIIT) on the health-related quality of life (HRQoL) in diabetic obese patients with nonalcoholic fatty liver disease (NAFLD). This study implemented a training program of 40 minutes of HIIT three times per week significantly improved the intrahepatic triglycerides (IHTG), VO2 max, visceral lipids, glycohemoglobin, blood glucose and all dimensions of HRQoL [6]. Additionally, a review by Westcott et al. in the American College of Sports Medicine 2012 discussed the plethora of benefits of resistance training on health. In addition to improvements to body weight, lean mass, and resting metabolic rate, resistance training positively influenced cognitive abilities and self-esteem [7]. Moreover, resistance training may help in the prevention and management of type 2 diabetes and improving insulin sensitivity. Resistance training may also have a positive effect on cardiovascular health due to its impact on reducing blood pressure, decreasing LDL-C, and increasing HDL-C [7].

The data regarding the positive effects of either aerobic training or resistance training on someone’s cardiovascular health and body composition is clear; however, several studies lately discussed the possibility of combining both aerobic and resistance training as they may have additional health benefits compared to each training type alone. A randomized controlled trial (RCT) done in 2012 studied the effect of either aerobic, resistance, or combined training types on body composition and risk of cardiovascular disease (CVD) in overweight and obese people during 12 weeks of moderate-intensity exercise. This study showed that combined exercise of 15 minutes of aerobic training coupled with 15 minutes of resistance training (five times a week) resulted in a significant decrease in body weight, body mass index, body fat percentage, and android fat percentage compared to control group (android fat is the fat or adipose tissues that are mainly distributed around the trunk and upper body area). No significance of the parameters above was shown in the aerobic or resistance group compared to the control group. The authors addressed the discrepancy in this study as compared to other studies. It might have to do with the nature of the intensity of these types of exercises. Higher intensity exercises might lead to significant changes in the studied parameters [8]. A study among individuals at high risk of developing CVD showed that an eight-week combination training program resulted in improved diastolic blood pressure, increased cardiorespiratory fitness, strength, and lean mass compared to either aerobic resistance training alone [9]. Another research studying the effect of the combined training regimen in dieting obese older adults showed that this type of training had positive effects on the physical performance, peak oxygen consumption, lean mass, strength, and body weight [10].

Although quite a few studies are suggesting that a combined training regimen might have better results on a person’s wellbeing, there are still a lot of people who believe that combining aerobic endurance training with resistance training is not a good idea. The reason behind this issue is a physiological and molecular effect called the “interference effect” or “concurrent training effect”. Briefly, several studies have suggested that endurance training coupled with resistance training in the same session would lead to attenuated muscle hypertrophy, strength, and power [11-13]. While other studies argue that this effect on strength and power is unwarranted [14, 15]. The details of this effect are out of the scope of our review today. However, a recent review in 2018 argued that the interference effect has no to low importance in people with a short training experience while having a higher influence on experienced participants [16]. Based on these studies and since most of the subjects from the randomized controlled trials we presented were sedentary people with little to no training background, we would argue that this interference effect would be of no to low importance in this review’s scope.

In conclusion, emerging studies and data are reaching a consensus that a combination of both resistance and aerobic training might be the step forward to achieving several key fitness components situated on the extreme opposites of the fitness spectrum. However, the exact details of combining both resistance and aerobic training, such as the intensity, the time allotted to resistance and aerobic exercises, the frequency, and many other factors are still unclear. Therefore, additional studies and data that focus on the same variables and parameters are still needed to elaborate on the exact effects of such a training regimen.

Table. A brief conclusion of the different studies and research discussed in the above review.

 Abbreviations: RCT, randomized controlled trials; y.o, years old; NAFLD, nonalcoholic fatty liver disease; HIIT, high-intensity interval training; VO2max, maximum volume of oxygen; LDL-C, low-density lipoprotein-cholesterol; HDL-C, high-density lipoprotein-cholesterol

References:
Geliebter, A., et al., Effects of strength or aerobic training on body composition, resting metabolic rate, and peak oxygen consumption in obese dieting subjects. The American journal of clinical nutrition, 1997. 66(3): p. 557-563.

Hsu, K.-J., et al., Effects of Exercise and Nutritional Intervention on Body Composition, Metabolic Health, and Physical Performance in Adults with Sarcopenic Obesity: A Meta-Analysis. Nutrients, 2019. 11(9): p. 2163.

Lee, S., et al., Effects of aerobic versus resistance exercise without caloric restriction on abdominal fat, intrahepatic lipid, and insulin sensitivity in obese adolescent boys: a randomized, controlled trial. Diabetes, 2012. 61(11): p. 2787-2795.

Lee, S., et al., Aerobic exercise but not resistance exercise reduces intrahepatic lipid content and visceral fat and improves insulin sensitivity in obese adolescent girls: a randomized controlled trial. American journal of physiology-endocrinology and metabolism, 2013. 305(10): p. E1222-E1229.

Lee, S., Y. Kim, and J.L. Kuk, What Is the Role of Resistance Exercise in Improving the Cardiometabolic Health of Adolescents with Obesity? Journal of obesity & metabolic syndrome, 2019. 28(2): p. 76.

Abdelbasset, W.K., et al., A randomized controlled trial on the effectiveness of 8-week high-intensity interval exercise on intrahepatic triglycerides, visceral lipids, and health-related quality of life in diabetic obese patients with nonalcoholic fatty liver disease. Medicine, 2019. 98(12).

Westcott, W.L., Resistance training is medicine: effects of strength training on health. Current sports medicine reports, 2012. 11(4): p. 209-216.

Ho, S.S., et al., The effect of 12 weeks of aerobic, resistance or combination exercise training on cardiovascular risk factors in the overweight and obese in a randomized trial. BMC public health, 2012. 12(1): p. 704.

Schroeder, E.C., et al., Comparative effectiveness of aerobic, resistance, and combined training on cardiovascular disease risk factors: a randomized controlled trial. PloS one, 2019. 14(1).

Villareal, D.T., et al., Aerobic or resistance exercise, or both, in dieting obese older adults. New England Journal of Medicine, 2017. 376(20): p. 1943-1955.

Wilson, J.M., et al., Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises. The Journal of Strength & Conditioning Research, 2012. 26(8): p. 2293-2307.

Dolezal, B.A. and J.A. Potteiger, Concurrent resistance and endurance training influence basal metabolic rate in nondieting individuals. Journal of applied physiology, 1998. 85(2): p. 695-700.

Häkkinen, K., et al., Neuromuscular adaptations during concurrent strength and endurance training versus strength training. European journal of applied physiology, 2003. 89(1): p. 42-52.

Fernandez‐Gonzalo, R., T.R. Lundberg, and P.A. Tesch, Acute molecular responses in untrained and trained muscle subjected to aerobic and resistance exercise training versus resistance training alone. Acta Physiologica, 2013. 209(4): p. 283-294.

Fyfe, J.J. and J.P. Loenneke, Interpreting adaptation to concurrent compared with single-mode exercise training: some methodological considerations. Sports Medicine, 2018. 48(2): p. 289-297.

Methenitis, S., A brief review on concurrent training: from laboratory to the field. Sports, 2018. 6(4): p. 127.