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The Health Benefits of Resistance Exercise: Beyond
Hypertrophy and Big Weights
Sidney Abou Sawan, Everson A. Nunes, Changhyun Lim, James McKendry, and Stuart M. Phillips
ABSTRACT
It is well established that exercise is associated with a reduced risk of several chronic diseases. Currently, aerobic training (AT) receives
primary attention in physical activity guidelines with a recommendation for ~150 minof moderate-to-vigorous AT weekly. In most phys-
ical activity guidelines, resistance training (RT) is termed a beneficial activity, with a recommendation to engage in strengthening activ-
ities twice weekly. However, we propose that the health benefits of RT are underappreciated. There is evidence, established and
emerging, that RT can, in many respects, elicit similar health benefits to AT. When combined, AT and RT may yield ostensibly optimal
health benefits versus performing either exercise exclusively. We discuss the health benefits of engaging in RT, including healthy aging,
improved mobility, cognitive function, cancer survivorship, and metabolic health in persons with obesity and type 2 diabetes—all of
which can influence morbidity and mortality. Many of the health benefits of RT can be achieved by lifting lighter loads to volitional failure,
highlighting that the benefits of RT do not necessarily require lifting heavier weights. Accumulating evidence also shows a lower mor-
tality risk in those who regularly perform RT. To optimize health, especially with aging, RT should be emphasized in physical activity
guidelines in addition to AT.
Keywords: skeletal muscle, type 2 diabetes, cancer, aging, cognitive function
INTRODUCTION
As a form of physical activity, exercise is generally dichotomized
into resistance training (RT) and aerobic training (AT) categories.
Although there is overlap between the two modalities, the intensity
and duration of exercise produce distinct molecular signals that re-
sult in divergent phenotypic adaptions (1). For example, the phe-
notypic adaptations associated with RT are underpinned by the
synthesis of new myofibrillar and mitochondrial proteins that in-
crease muscle size and endurance, respectively (1). Prescription of
RT and AT programs is often based on a relative percentage of max-
imal strength (i.e., single-repetition maximum (1RM)) and oxygen
consumption (i.e., peak oxygen uptake (V
˙O
2peak
)ormaximum
heart rate (HR
max
)). For example, lifting heavier loads (>70% of
1RM) of RT is recommended to build muscle mass (2), whereas
both moderate-intensity continuous exercise (~70% of HR
max
)
and high-intensity interval training (~85%–90% of HR
max
)canin-
duce AT adaptations (3). However, there is emerging evidence that,
in addition to increasing muscle size and strength, RT can induce
mitochondrial adaptations that are typically associated with AT
(4). For example, performing RT with lower loads (i.e., ~30% of
1RM) to volitional fatigue induces an increase in mitochondrial
proteins and muscle oxidative capacity (4). Importantly, lower
load RT offers an alternative to RT with heavier loads in popula-
tions in which traditional RT is neither preferred nor warranted
(e.g., aging, cancer). To reduce chronic disease risk, AT remains
at the forefront of physical activity guidelines, highlighted by a
prescription of ~150 min of moderate-to-vigorous or 75 min of
vigorous AT weekly (5). Although RT is recommended in the
current physical activity guidelines, there is emerging evidence
demonstrating that RT alone or when combined with AT is
equal or superior to AT alone in maximizing health. Here, we
highlight some of the numerous health benefits of RT (Fig. 1),
which extend far beyond muscle hypertrophy and the require-
ment to lift heavy weights.
MOBILITY AND FALLS
The global population is aging, and those older than 70 yr are the
most rapidly expanding population demographic. Aging is associ-
ated with sarcopenia, the age-related loss in muscle mass, strength,
and function, which is inversely related to morbidity and mortality
(6). The treatment costs associated with sarcopenia in the US
health system are ~$19 billion per year in direct (e.g., hospitaliza-
tion due to falling) and indirect (e.g., injury-related work disabil-
ity) costs (7). Severe falls reduce the quality of life and exacerbate
cognitive function declines, which reduce independence (8). Im-
portantly, lifelong physical activity can help attenuate declines in
muscle mass and strength (6). Unsurprisingly, RT improves
Department of Kinesiology, McMaster University, Hamilton, Canada
Addressfor correspondence:Stuart M. Phillips, Ph.D., FACSM, FCAHS,De partment of K inesiology, Mc Master Univers ity, 1280 Main Street West, Hamilto n, Ontario, Ca nada
(E-mail: phillis@mcmaster.ca).
Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.
This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.
How to cite this article: Sidney Abou Sawan, Everson A. Nunes, Changhyun Lim, James McKendry, Stuart M. Phillips. The Health Benefits of Resistance Exercise: Beyond
Hypertrophy and Big Weights. Exerc Sport Mov 2022;1(1):e00001.
Received: July 27, 2022 / Accepted: September 21, 2022.
http://dx.doi.org/10.1249/ESM.0000000000000001
Graphical Review
1
mobility in the elderly and combining RT and AT (along with bal-
ance training) effectively reduces falls in care facilities (9,10). How-
ever, AT alone does not promote the muscle mass and strength
gains seen with RT (11). The question is, are heavier loads re-
quired in an RT program designed to reduce fall risk? The answer
is likely no, because lower load RT combined with balance train-
ing effectively mitigates fall risk (8).
COGNITIVE FUNCTION
In addition to declines in muscle mass, it is well established that de-
clines in cognitive function accompany aging. The risk of cognitive
decline is exacerbated by inactivity (12). Evidence indicates that in-
creasing physical activity can affect cognitive function in older
adults and individuals with mild cognitive impairment (13). The
effects of RT on cognition may be mediated by exercise-induced
increases inbrain-derived neurotrophic factors and cerebral blood
flow, which are associated with improved cognition (14). How-
ever, most current research has demonstratedthat AT positively af-
fects executive functions (e.g., focus, attention, and multitasking) and
memory, with little focus on RT alone (15). Recent meta-analyses have
demonstrated positive effects of RT on age-related executive cognitive
ability and global cognitive function, but not working memory (15).
Indeed, manipulation of RT variables (i.e., frequency, volume, and
duration) may affect cognitive improvements in older adults. For ex-
ample, compared with a nonexercised control group, RT performed
twice a week for long periods (≥16 wk) and at moderate intensity
(50%–70% 1RM) is more likely to improve overall cognitive func-
tion in cognitively healthy older adults (13). Notably, positive effects
of cognition can manifest in RT programs lasting less than 16 wk in
older adults who are cognitively impaired (13). Thus, improving cog-
nitive function with RT could positively impact quality of life in the
elderly (Fig. 2).
CANCER
Cancer is among the leading causes of death in several countries.
Cancer and its therapies are associated with many negative im-
pacts, including reductions in muscle mass and strength. Cachexia
is a complex metabolic syndrome more frequently associated with
some types of cancer (e.g., lung, pancreatic, and gastric) and other
chronic diseases (e.g., chronic obstructive pulmonary disease and
human immunodeficiency virus/acquired immunodeficiency syn-
drome) (16). Because age is a risk factor for many cancers, there
is a possibility that sarcopenia and cachexia occur concurrently.
Cancer cachexia is partially mediated by tumor-induced systemic
inflammation that promotes catabolism (16). Changes in body
composition during cancer can also be exacerbated by the direct
effects of treatment (i.e., chemotherapy, radiation, and surgery)
and indirect lifestyle changes such as physical inactivity and de-
creased nutritional intake. Because cancer is a heterogeneous dis-
ease, the type and stage of cancer and variations in treatment type
Figure 1. Health adaptations resulting from regularly engaging in resistance training (RT) versus aerobic training (AT) in addition to the concurrent effectsofAT+RT.
Exercise, Sport, and Movement
2
(e.g., number of therapies, duration of treatment, and dose of ther-
apies) may affect muscle loss. During multimodal treatment in
cancer patients, body composition changes are characterized by
a decrement in lean mass and relative increases in fat mass (16).
Paradoxically, a higher body mass index (primarily attributed to
an increase in adiposity) in patients with certain cancers reduces
mortality compared with cancer patients with low normal body
mass index (17). We propose that this observation may be due
to greater muscle mass independent of changes in fat mass.
However, depending on the therapy and type of cancer, cachexia
can also occur because of decrements in food intake (16). Not-
withstanding changes in fat mass, low muscle mass is associated
with a higher risk of cancer recurrence, overall and cancer-specific
mortality, surgical complications, and cancer treatment-related
toxicities (17).
Physical activity has been shown to have clinically significant
benefits for people with cancer, including improvements in physi-
cal and psychosocial function, fatigue resistance, improved quality
of life, reduced recurrence, and increased survival (18) (Fig. 3).
RT alone or combined with AT is superior to AT alone in reduc-
ing all-cause and cancer-specific mortality (19,20). Thus, RT has
promising potential to counteract the adverse side effects of can-
cer, such as muscle wasting. Cancer patients who undergo treat-
ment can experience cachexia and higher chemotherapy-related
toxicity, whereas patients who begin therapy with greater muscle
mass experience fewer toxicities and better clinical outcomes
(17). RT does not appreciably affect lean body mass during cancer
treatment; however, the preservation of muscle mass induced by
RT is associated with a reduced risk of all-cause mortality in can-
cer survivors (18).
METABOLIC HEALTH
Obesity and type 2 diabetes (T2D) are linked diseases hallmarked
by higher body fat and hyperglycemia and insulin resistance, re-
spectively. Physical inactivity, weight gain, andadipose tissue mass
are hallmarks of obesity and often T2D. Sarcopenia and inactivity
are proposed to be primary drivers of insulin resistance and T2D
development (6,21). Although obese people have more muscle
mass than their normal-weight counterparts (17), inactivity, rather
than increasing muscle mass per se, seems to be the predominant
driver of insulin resistance (6). Engaging in physical activity while
overweight, irrespective of weight loss (22), is an effective strategy
for managing obesity and T2D. In addition to exogenous insulin
and drugs, AT has conventionally been recommended to treat obe-
sity and T2D (23). However, there is no clinically significant dif-
ference between RT and AT in lowering hemoglobin A
1c
or other
T2D-relevant health outcomes (23). Indeed, a recent meta-analysis
has shown that RT is effective in reducing fat mass in overweight/
obese older adults (24). Also, low–moderate-intensity resistance
Figure 2. Effects of (in)activity and resistance training on physical and cognitive function across the lifespan.
Figure 3. Impact of resistance training to enhance physical function, quality of life, and cancer survivorship.
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3
exercise (i.e., 50%–75% 1RM) improves acute postexercise lipid
profiles (25). Combining RT and AT seems to be superior in managing
T2D and obesity (26,27). Furthermore, chronic RT improves glyce-
mic control in elderly patients with T2D (21). To this end, diabetic
and sarcopenic skeletal muscle have very similar metabolically in-
flexible profiles (28). Thus, it may be that RT can induce adaptations
to improve metabolic health, including muscle protein remodeling,
mitochondrial oxidative capacity, and heightened insulin sensitivity
(1,21,29) (Fig. 4). These data suggest that AT or RT can improve
metabolic health irrespective of increasing muscle mass.
MORTALITY
A few cohort and review studies have emerged showing that mor-
tality from all causes, T2D, cancer (all types and some subtypes),
and cardiovascular diseases is reduced with participation in RT,
independent of AT (30–33). Performing 1–2 sessions per week or
the equivalent of 60–120 min·wk
−1
has shown consistent effect in de-
creasing all-cause mortality, with weak associations for cancer- and
cardiovascular disease–related mortality. Nevertheless, Momma et al.
(32) reported that the practice of RT beyond ~130–140 min·wk
−1
re-
sulted in an increased relative risk of all-cause, cardiovascular, and
cancer mortality (33). Both studies also stated that such increment
might be more prone to happen because of cardiovascular events,
and speculate that the effects of RT increasing arterial stiffness might
play a role in such phenomena (32,33). Notably, these authors cau-
tioned that the number of studies showing such unexpected outcome
is low, and further studies are needed to address this hypothesis
(32,33). Furthermore, Momma et al. (32) found that the maximum
risk reduction for all-cause, cardiovascular, and total cancer mortality
was with ~30–60 min·wk
−1
of RT. In contrast, the risk of T2D mortality
decreased sharply up to 60 min·wk
−1
of RT (32). The optimal dose of RT
to reduce all-cause and disease-specific mortality remains to be determined.
CONCLUSIONS
The health effects of RT extend beyond those attributed to increas-
ing muscle mass and strength and include reduced mortality risk
(30–33). Participation in RT can increase physical and cognitive
function, improve cancer survival, and manage metabolic health.
We propose that RT be placed at the forefront of physical activity
guidelines alongside AT. However, we are mindful that adoption
of and adherence to RT in clinical populations remains low; the
most cited barriers to engaging in RT are risk of injury (the risk
for which may be reduced when lifting lighter relative loads) and
required access to a gym facility (34). Notably, the prevention of
disability, reduced risk of falls, and improving cognitive ability are
potential health motivators for engaging in RT (34). We recommend
performing RT with light-to-moderate relative loads (≥30% but
<70% of 1RM) or using only body weight as resistance. Repetitions
within a given set should be performed to the point that results in a
high degree of effort or relatively close to momentary muscular fail-
ure (35). Such RT routines are just as effective as lifting relatively
heavy loads (≥70% of 1RM) for eliciting health benefits. This point is
of particular importance, especially in the context of events that impose
episodic muscle disuse in response to illness or limb immobilization/
surgery, which accelerates the ~1% and ~3% loss per year of muscle
and strength, respectively, in those older than 60 yr (6). A larger skeletal
muscle reservoir preceding such disuse events would be protective and
could ostensibly improve recovery and maintain mobility/metabolic
health. Future research should examine the optimal dose and intensity
of RT, combined with or without AT, required to optimize health
benefits and reduce mortality risk.
ACKNOWLEDGMENTS
The results of the current study do not constitute endorsement by
the American College of Sports Medicine.
CONFLICTS OF INTEREST AND SOURCE OF FUNDING
S. M. P. reports grants or contracts from the US National Dairy
Council, Dairy Farmers of Canada, Roquette Freres, and Nestle
Health Sciences in the previous 5 yr or during the conduct of the
study and personal fees from US National Dairy Council and non-
financial support from Enhanced Recovery outside the submitted
Figure 4. Impact of (in)activity and resistance training on whole-body and muscle metabolic health.
Exercise, Sport, and Movement
4
work. S. M. P. has patent (Canadian) 3052324 assigned to Exerkine
and patent (US) 20200230197 pending to Exerkine but reports no
financial gains from any patent or related work.
E. A. N. is a tier 2 Research Productivity Fellow supported by
the Brazilian National Council for Scientific and Technological
Development (grant number 308584/2019-8). S. M. P. is tier 1
Canada Research Chair and acknowledges the funding from that
agency. S. M. P. also holds grants from the National Science and
Engineering Council of Canada (RGPIN-2020-06346) and the
Canadian Institutes of Health Research.
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