Key words
breast cancer - exercise - cancer - ressitance training
Introduction
Obesity is a risk factor for both breast cancer and disease recurrence after
treatment [1]. Furthermore, weight gain during
and after treatment for breast cancer is associated with a higher risk of
recurrence, distant metastases, and death [2].
Yet, most women gain significant weight during and after breast cancer treatment,
potentially compromising outcomes.
Conversely, increased activity levels have been repeatedly associated with decreased
breast cancer incidence as well as improved outcomes after breast cancer treatment,
including breast cancer-specific and overall survival [3]. Many breast cancer survivors do not meet
adequate daily activity level recommendations, potentially compounding issues with
weight gain during and after breast cancer treatment [4]. As a result, attempts are underway to both
quantify and increase activity levels during treatment and survivorship [5].
Studies in non-cancer populations reveal that aerobic exercise, when unaccompanied by
other health changes, is generally minimally effective for weight loss, and
specifically fat loss [6]. Breast cancer
survivors achieving weight loss through aerobic exercise may risk loss of lean mass
and muscle tissue [7] and the potential
metabolic and functional benefits that accompany both. In contrast, resistance
training at an appropriate intensity level may help support lean mass maintenance or
even muscle gains during weight loss, which has been shown to simultaneously
increase resting metabolic rate to increase fat oxidation and improve body
composition [8]
[9]. Such changes may be more advantageous in
the oncologic setting than previous aerobic-based exercise strategies to increase
caloric expenditure.
Historically, resistance training regimens among breast cancer survivors limited
training intensity and progression in an effort to minimize the risk of exacerbating
treatment-related lymphedema [10]. Yet,
multiple studies have now confirmed no increase, and potentially improvement, in
lymphedema in women undergoing resistance training after breast cancer treatment
[11]
[12]
[13]
[14]. For safety measures, many home
interventions in breast cancer patients also utilize light-weight free-weight, or
open kinetic chain (OKC) movements where the body is fixed and the distal
extremities are mobile, both of which can often limit activation of core and
accessory muscles, leading to a less intense regimen that may limit functional and
mobility benefits and hypertrophy [15]
[16]. Closed kinetic chain (CKC) exercises, also
known as compound exercises, involve fixation of the distal aspect of the extremity
(as opposed to proximal isolation) and therefore require involvement of multiple
joints and co-contraction of multiple simultaneous muscles to stabilize the body
during movement. Such CKC exercises include lunges, squats, deadlifts, and power
cleans; in contrast, examples of OKC exercises are bench press, seated leg curls and
extensions, and machine curls. Closed kinetic chain and compound exercises also
mimic athletic movements, thus positively impacting mobility and function.
Studies in non-cancer patients reveal that resistance training routines that expose
muscle tissue to extensive mechanical tension with subsequent muscle damage and
metabolic stress promote training-induced muscle growth [17]. Resistance training has been shown to
combat cachexia and augment muscle mass in individuals with cancer via an array of
mechanisms [18]. While resistance training has
shown significant improvements in quality of life after treatment for cancer,
reports on improvements in body composition have been underwhelming thus far [19].
While weight training has clear advantages over aerobic training for improving body
composition and several measurable metabolic variables, there have been barriers to
its implementation in exercise regimens for the breast cancer patient, including
concerns of safety and lymphedema risk [20].
However, as stated above, these risks have been largely disproved by the current
available research [21]. Adverse effects (AEs)
reported in prior exercise studies include typical self-limiting musculoskeletal
issues, including muscle strains, joint and back pain, shin splints, and tendinitis
[22]. Overall, AEs are minimal.
Furthermore, an observed environment with supervision by trained exercise personnel
can further reduce the risk of injury [23]
[24], as can adaptation of a
workout regimen that accounts for individuals’ functional movement
abilities, mobility, and function [25].
Additionally, studies reveal that observed exercise programs lead to enhanced
strength gains and hypertrophy [26], and
successful exercise interventions tend to be those that involve direct supervision
[27]. Finally, many of the exercise
regimens tested include prolonged exercise regimens like treadmill and aerobic
sessions lasting 90 minutes or more. More intense weight training generally lasts a
fraction of the time and therefore may serve as a time-effective method of
exercise.
Thus, the EXERT-BC protocol (a prospective study of an exercise regimen designed to
improve functional mobility, body composition, and strength after treatment for
breast cancer) was designed to assess the safety and feasibility of an observed
exercise regimen utilizing high-load resistance training via compound CKC and
functional resistance exercises with the goal of improving physical and metabolic
function, mobility, muscle mass, and body composition in women with breast cancer
utilizing guidelines from the National Strength and Conditioning Association (NSCA).
Herein, we report an interim analysis of body composition and exercise parameters
for an initial cohort following an initial three-month resistance training
regimen.
Methods
Participants
Women aged 20–89 with biopsy-proven ductal carcinoma in situ (DCIS) or
breast cancer were eligible for this trial. Additionally, participants were
required to be able to get up and down from the ground, squat their body weight,
and be able to participate in a group exercise regimen. Individuals with severe
arthritic, joint, cardiovascular, or musculoskeletal condition deemed unsafe to
engage in resistance training were excluded. Participants currently treated with
systemic cytotoxic chemotherapy were excluded from the study, while radiation
therapy, anti-estrogen and targeted systemic therapy were allowed. Participants
were screened by study personnel at the time of oncologic consultation or
follow-up. Treatment and medical records were manually curated.
Recruitment occurred between September 15, 2022, and April 13, 2023, at the
Allegheny Health Network (AHN) departments of surgical, medical, and radiation
oncology, along with the AHN Cancer Institute Exercise Oncology and Resiliency
Center. Consent was obtained for each participant. The study was approved by the
institutional review board (protocol 2022–269-SG) and registered at
ClinicalTrials.gov (NCT05747209).
Experimental design
All participants were enrolled in a 3-month thrice-weekly dose-escalated exercise
regimen utilizing multi-joint compound movements and linear progression balanced
with resistance training volume to elicit hypertrophy, as previously published
[28]. The co-primary outcomes were
regimen adherence and safety, which were recorded throughout the regimen.
Secondary endpoints, reported in the present interim analysis, included change
in body composition, functional mobility, and balance, resting metabolic rate,
phase angle, quality of life, and activity levels.
Body composition and resting metabolic rate
Prior to initiation of the exercise regimen and at completion, each participant
underwent body composition analysis via an InBody 970 bioimpedance analysis
(BIA) machine (InBody Co., Seoul, South Korea). InBody testing is noninvasive
and requires no ionizing radiation. The individual simply stands on the machine
while holding handles. Reliability and agreement of the InBody device is high
with small error risk [29]. To confirm
changes over differing modalities, an ultrasound (US) was also utilized to
measure muscle and adipose tissue thickness to provide additional metrics for
body composition with fat mass, fat-free mass, percent body fat, and resting
metabolic rate calculated utilizing BodyMetrix software (BodyMetrix, Brentwood,
CA, USA) and measurements at the triceps, suprailiac, abdominal, and thigh area
utilizing the Jackson & Pollock calculation[30]. US is a valid and reliable method to
assess body composition [31]
[32]. Both devices utilize the body metrics
and Cunningham equation to calculate resting metabolic rate, which has been
shown to be relatively accurate [33].
Functional movement and balance
Prior to initiation of the exercise regimen and at completion, each participant
underwent a seven movement Functional Movement Screen (FMS) and Y-balance test.
The FMS is a tool used prior to the initiation of an exercise protocol to assess
individual mobility and movement patterns. These patterns are general
accompanied by compensatory mechanisms that may predispose participants to
injury but can be improved through specific exercises that can reduce the risk
of chronic injury. During the test, seven movement patterns are assessed and
each one is rated between 0 and 3 by an examiner. These movements include the
deep squat, hurdle step, inline lunge, shoulder mobility test, active straight
leg raise, trunk stability push up, and rotary stability test. Normal values in
the general population range from a score of 12.56 in individuals over the age
of 65 to 14.79 in individuals aged 20–39, and women generally have a
slightly higher score [34]. The FMS has an
acceptable degree of inter-rater reliability and is currently the most
well-researched movement screen available.
The Y-balance test has the participant stand on one leg while reaching out in
three different directions with the other lower extremity. They are anterior,
posteromedial, and posterolateral. When using the Y-Balance test kit, the three
reaches yield a “composite reach distance” or composite score
used to predict injury.
Strength and load lifted
Prior to initiation of the exercise regimen and at completion, each participant
underwent bilateral grip strength assessment with the arm in the neutral
position and overhead utilizing a Jamar Hand Dynamometer grip strength
measurement device (Patterson Medical, Warrenville, IL, USA). Load was
calculated continuously and throughout the regimen as volume load and by
multiplying weight lifted (lbs) by repetitions and sets. These calculations
occurred at the fourth week of the exercise regimen to ensure proper form,
movement, and adaptation to the exercise, and then again at the eighth and final
week of the exercise regimen. Split squat, trap bar deadlift, incline dumbbell
bench press, and bird dog row were compared as these encompass squat, hip hinge,
push, and pull movement patterns.
Quality of life and activity levels
Prior to initiation of the exercise regimen and at completion, each participant
completed EQ-5D-5L and Godin Leisure-Time Exercise Questionnaires, which
strongly correlate with activity levels and quality of life [35].
Phase angle
Phase angle, which reflects the health of cellular membranes, was assessed via the
InBody 970 bioimpedance analysis (BIA) machine (InBody Co., South Korea).
Exercise intervention
The exercise regimen utilized a mixture of compound movements focusing on CKC
movements, utilizing linear progression, and following guidelines from the NSCA.
Each individual exercise workout progressed from most intense, CKC, compound,
and athletic movements like squats and dead lifts, to least intense and more
isolated exercises throughout the workout to maximize safety. Additionally, each
workout provided full body resistance training focusing on the basic movement
patterns of push, pull, hip hinge, squat, and core activation. The entire
program lasted 3 months, and each exercise session ranged from 45–60
minutes. Activation and reset exercises focusing on mobility, muscle activation,
and range of motion were performed prior to each workout to reduce the risk of
injury. There was a 2-week ramp up period at the start of the program, and
weights lifted utilized a combination of repetition speed, number “left
in the tank”, and rating of perceived exertion (RPE). See [Fig. 1] for an example of the program.
Fig. 1 Workout regimen during month one.
The study took place at the Exercise Oncology and Resiliency Center. The center
is a state-of-the-art 3,000-square-foot exercise and research facility where the
exercise regimens are created and monitored by Certified Strength and
Conditioning Specialists (CSCSs) utilizing exercise principles to improve
strength, conditioning, performance, and overall health.
Exercise class attendance was recorded for each class. Planned missed days were
able to be performed remotely if the individual had access to similar workout
equipment only after the first month of the regimen. The initial 2 weeks of the
regimen were considered the run-in period with strength and movement assessments
to help ascertain proper weight usage and individual lifts. Exercises were
progressed or regressed around specific core movement patterns (push, pull, hip
hinge, squat, and core). For example, if an individual was unable to split squat
body weight, they would be assisted in the movement until they could progress to
the weighted lift. Weight lifted, repetitions, sets, and notes were recorded,
and load was calculated throughout (volume load=weight
lifted×repetitions×sets).
Statistics
All of the anthropometric, metabolic, fitness and QOL measurements were analyzed as
continuous variables. Pairwise comparisons were assessed via the Wilcoxon
signed-rank test. For each compound exercise, total load across months 1–3
was assessed via the Freidman test, with intragroup comparison using Wilcoxon signed
rank testing with Bonferroni correction. All statistical analyses were performed
using R version 4.1.2 (R Project for Statistical Computing).
Results
In total, 52 women were referred to the EOC to be screened for this study. Nine did
not choose to participate, with the most common reason being work and scheduling
conflict. Two were referred to physical therapy due to concerns of joint impingement
or musculoskeletal disorders. Forty women were enrolled in the study, and the first
twenty have completed the exercise regimen. Patient characteristics are listed in
[Table 1]. Mean age was 57 (range
41–74) and half of the participants were diagnosed with DCIS or early-stage
breast cancer. Nearly 75% were undergoing treatment with anti-estrogen
therapy during the study, and 23% were actively receiving irradiation.
Twenty-seven percent of participants had engaged in prior exercise before enrolling
and all participants continued a resistance training regimen after the protocol.
Table 1 Patient characteristics.
|
Age, years (mean, range)
|
57
|
41–74
|
|
Breast cancer stage
|
N=20
|
|
|
DCIS
|
1
|
(5%)
|
|
Early stage
|
10
|
(45%)
|
|
Locally advanced
|
7
|
(32%)
|
|
Locally recurrent
|
3
|
(14%)
|
|
Metastatic
|
1
|
(5%)
|
|
Lymphedema
|
N=5
|
(23%)
|
|
Worse
|
0
|
(0%)
|
|
Better
|
1
|
(5%)
|
|
Concurrent Therapies
|
N=24
|
|
|
Antiestrogen
|
16
|
(73%)
|
|
Chemotherapy
|
3
|
(14%)
|
|
Radiotherapy
|
5
|
(23%)
|
|
Prior Exercise
|
N=6
|
(27%)
|
|
Coach Rating (mean, SE)
|
2.45
|
0.14
|
DCIS, ductal carcinoma in situ; SE, standard error.
Adherence at interim analysis revealed 1.75 missed classes per participant (range
0–7), with all 20 participants meeting adherence over 75%. No
injuries or adverse events were reported, besides muscle soreness and, in one
participant, 2 days of knee pain.
Body composition
Large improvements were seen in body composition in both BIA and US ([Table 2]). On BIA, mean body fat percent
decreased from 38.22±2.0 to 36.66±2.5 (p=0.003) and body fat
(lbs) decreased from 72.60±6.56 to 68.22±6.89 (p=0.020).
Muscle mass (lbs) and percent muscle mass increased from
58.04+/–1.66 to 59.58+/–1.63
(p=0.002) and 33.07+/–1.22 to
37.14+/–2.27 (p < 0.001), respectively. On US,
percent body fat decreased from 37.19+/–1.30 to
32.7+/–1.42 (p < 0.001), while fat free mass
increased from 28.73+/–1.20 to
31.66+/–1.15 (p=0.011). Bone mineral concentration
was maintained throughout the regimen with no changes.
Table 2 Mechanisms of interaction between exercise and
improved cancer-specific outcomes.
|
Baseline
|
Month 3
|
|
|
Mean
|
SE
|
Mean
|
SE
|
Wilcoxon signed-rank p value
|
|
Height (inches)
|
65.11
|
0.44
|
-
|
-
|
-
|
|
Weight (initial)
|
177.38
|
8.54
|
176.93
|
8.88
|
0.834
|
|
InBody body fat (lbs)
|
72.60
|
6.56
|
68.22
|
6.89
|
0.020
|
|
InBody body fat%
|
38.22
|
2.00
|
36.66
|
2.15
|
0.003
|
|
InBody muscle mass (lbs)
|
58.04
|
1.66
|
59.58
|
1.63
|
0.002
|
|
InBody muscle mass%
|
33.07
|
1.22
|
37.14
|
2.27
|
<0.001
|
|
InBody fat-free mass
|
106.79
|
3.41
|
108.72
|
2.79
|
0.108
|
|
BMC
|
6.45
|
0.17
|
6.48
|
0.17
|
0.223
|
|
Whole-body phase angle
|
4.85
|
0.11
|
5.11
|
0.12
|
0.011
|
|
US% BF
|
37.19
|
1.30
|
32.7
|
1.42
|
<0.001
|
|
US essential fat (lbs)
|
53.34
|
2.87
|
53.9
|
3.67
|
0.442
|
|
US excess fat
|
13.22
|
2.93
|
9.68
|
2.5
|
0.108
|
|
US FFM
|
28.73
|
1.20
|
31.66
|
1.15
|
0.011
|
|
InBody RMR
|
1426.41
|
30.81
|
1435.05
|
27.42
|
0.108
|
|
US RMR
|
1440.27
|
36.81
|
1513.32
|
41.6
|
0.017
|
|
Grip strength RH
|
19.50
|
1.16
|
22.73
|
0.93
|
0.261
|
|
Grip strength RL
|
23.32
|
1.30
|
24.77
|
0.99
|
0.304
|
|
Grip strength LH
|
20.27
|
1.16
|
23.82
|
1.16
|
0.016
|
|
Grip strength LL
|
21.68
|
1.32
|
24.68
|
1.09
|
0.143
|
|
Godin
|
27.36
|
5.07
|
38.41
|
2.42
|
0.152
|
|
EQ5D1
|
4.91
|
0.06
|
4.86
|
0.1
|
1.000
|
|
EQ5D2
|
5.00
|
0.00
|
5
|
0
|
-
|
|
EQ5D3
|
4.91
|
0.06
|
4.86
|
0.07
|
1.000
|
|
EQ5D4
|
4.36
|
0.14
|
4.23
|
0.17
|
0.824
|
|
EQ5D5
|
4.68
|
0.10
|
4.82
|
0.08
|
0.773
|
|
EQ5D6
|
73.09
|
4.42
|
81.95
|
3.51
|
0.097
|
|
FMS initial
|
9.82
|
0.51
|
11.73
|
0.7
|
0.018
|
|
Y-balance L
|
72.37
|
2.69
|
85.26
|
2.4
|
0.001
|
|
Y-balance R
|
70.33
|
2.60
|
85.24
|
2.42
|
<0.001
|
SE, standard error; BMC, bone mineral concentration; US, ultrasound; lbs,
pounds; FFM, fat-free mass; RH, right high; RL, right low; LH, left high;
LL, left low; FMS, functional movement screen.
Resting metabolic rate (kcal/day) was unchanged on BIA but was increased from
1440.27+/–36.81 to 1513.32+/–41.6
(p=0.017) on US. Additionally, phase angle was increased 4.85 to 5.11
(p=0.011).
Functional movement and balance
Functional movement and balance
Significant improvements were seen in balance and functional movement. Mean FMS
scores increased from 9.82+/–0.51 to
11.73+/–0.7 (p=0.018). Mean Y-balance on the left
increased from 72.37+/–2.69 to
85.26+/–2.4 (p=0.001) and mean Y-balance on the
right increased from 70.33+/–2.60 to
85.24+/–2.42 (p < 0.001).
Strength and load lifted
Significant increases were seen in strength and load lifted on conclusion of the
exercise regimen ([Table 3], [Fig. 2]). Hand grip strength did not
significantly change except on the left with arm overhead (p=0.016). Load
calculations for split squat, trap bar deadlift, bird dog row, and incline dumbbell
press increased significantly throughout the workout, with mean deadlift loads of
2900 lbs. For all compound exercises, the Friedman test was significant with an
overall difference in load across months 1, 2, and 3. Accordingly, pairwise
comparisons were performed, showing significant increase in load from completion of
month 1 to month 3 for each exercise even after multiple hypothesis correction
([Table 3], [Fig. 2]).
Fig. 2 Load lifted over time (sets x repetitions x lbs), shown at the
end of each successive month of training as mean values with standard error
bars. Abbreviations: *P<0.05;
**P<0.001 on pairwise Wilcoxon signed-rank testing
with Bonferroni correction.
Table 3 Changes in load lifted, reported as mean and standard
error. Following Friedman testing with p<0.05, pairwise
comparisons across months 1 vs. 3, 1 vs. 2, and 2 vs. 3 were performed
via Wilcoxon signed rank testing with Bonferroni
correction.
|
Month 1
|
Month 2
|
Month 3
|
p value
|
|
Exercise
|
Mean
|
SE
|
Mean
|
SE
|
Mean
|
SE
|
Month 1 vs. 3
|
Month 1 vs. 2
|
Month 2 vs. 3
|
|
Split squat
|
383.0
|
89.4
|
782.4
|
84.8
|
951.0
|
123.9
|
<0.001
|
<0.001
|
0.268
|
|
Trap bar DL
|
2363.4
|
117.4
|
2576.1
|
189.9
|
2913.0
|
195.2
|
0.035
|
0.238
|
0.155
|
|
Incline DB bench
|
341.4
|
34.5
|
538.2
|
37.1
|
673.3
|
69.7
|
<0.001
|
<0.001
|
0.047
|
|
Bird dog row
|
374.2
|
36.3
|
523.9
|
43.4
|
725.2
|
40.4
|
<0.001
|
<0.001
|
0.002
|
SE, standard error; DL, dead lift; DB, dumbbell.
Quality of life and activity levels
Quality of life and activity levels
Godin levels of activity increased from 27.36+/–5.07 to
38.41+/–2.42, but this was not statistically significant.
Quality of life scores were similarly high for EQ-5D questions before and after
exercise, though with a numeric increase in self-rating of heath from
73.09+/–4.42 to 81.95+/–3.51
(p=0.097).
Phase angle
Phase angle increased from 4.85+/–0.12 to
5.11+/–0.12° (p=0.011).
Discussion
Interim analysis of the EXERT-BC study assessing a novel dose-escalated resistance
training regimen for women with breast cancer reveals significant and impactful
improvements in balance, functional movement, strength, muscle mass, and fat mass,
even though half of participants had locally advanced, recurrent, or metastatic
breast cancer. This was achieved in a short period of 3 months utilizing an intense
linear progression resistance training regimen with a focus on multipoint movement
compound and closed chain exercises.
In comparison to prior studies, these data reveal considerable increase of muscle
mass with an average increase of 1.5 lbs. of muscle mass on BIA and 3 pounds of
fat-free mass on US [36]. With the
considerable amount of adipose tissue lost during the intervention, percent body fat
dropped 2.5 and 4.5% on BIA and US, respectively. Additionally, phase angle
was significantly improved after the resistance training regimen ([Table 3]). Phase angle reflects the health of
cellular membranes and muscle function and correlates with outcomes after the
treatment for cancer [37]. Significant
improvement was seen in phase angle in just 3 months of resistance training, raising
the question as to whether this one mechanism exercise may improve cancer-specific
outcomes [38].
The age and functional status of the women in this study varied significantly, with a
minority already engaged in a resistance training or exercise regimen prior to
enrollment in the protocol. Additionally, the majority had chronic musculoskeletal,
joint, or orthopedic issues yet were capable of engaging in an intense exercise
regimen utilizing compound movements and heavy weights. Half of the women were
experiencing joint pain from endocrine therapy or lymphedema from axillary surgery
on enrollment in the study. Yet, the load lifted was able to produce significant
increases in strength and considerable improvements in functional movement
assessments and balance scores, the latter of which improved by around 20%
for each leg. Such profound changes could have large downstream impact on both
health and cost-saving by reduced risk of falls and fractures and generally improved
overall physical function, which correlates strongly with outcomes after the
treatment of breast cancer, particularly within the first two years after
treatment.[39] Of note, lymphedema did not
worsen in any participants and improved in one based on fluid measurements (data not
shown).
A recent large study published in the Journal of Clinical Oncology found that
breast cancer patients randomized to a strength training regimen did not exhibit a
reduced fall risk [40]. However, their weight
training regimen utilized 1–3 sets of 8–10 exercises at a weight
performed at 8–12 repetitions with weighted vests providing resistance, with
planned progression increases of 1–3% body weight up to a target of
15% by 6 months. Several similar regimens appear within the breast cancer
exercise oncology literature utilizing low loads [41]. In EXERT-BC, we aimed to stress the neuromuscular and
musculoskeletal systems with linear progression to elicit the maximum potential
neuroadaptation and increase in strength utilizing a regimen that has shown benefits
in noncancer patients. Additionally, the present regimen was designed to achieve
around 10 sets per muscle group or movement pattern per week, as studies reveal this
may promote hypertrophy [42].
While the above is an interim assessment of EXERT-BC, it may suggest that a higher
dose of resistance training utilizing compound multi-joint movement may be more
efficacious in improving functional capacity and reducing fall risk.
It is important to note that studies in noncancer and athletic populations have
revealed doses of exercise that are generally required to elicit physical
improvements like increases in bone density, muscle mass, and strength [28]. Data reveal that these thresholds are
rarely met in exercise oncology literature. Other data have questioned whether women
with a history of breast cancer or undergoing treatment for breast cancer may
achieve similar physiologic changes to those of a noncancer population [36]. The data from the interim analysis of
EXERT-BC appear to support this hypothesis.
Limitations of the study should be addressed. Firstly, this was a single arm study
with no comparison or control group, future studies should include a randomization.
Assessing body composition while maximizing terms of safety, efficacy, convenience,
and cost is difficult. All sources, including bioimpedance analysis and ultrasound,
have limitations. However, to minimize these issues, we performed both tests to
confirm consistent changes across two modalities. The average age was 57 years, so
the results of this study may not be applicable to all individuals with breast
cancer. Additionally, the training age of the participants was quite low, and most
had never engaged in prior resistance training. However, it should be noted that
entrance criteria were broad, with the major stipulation being the ability to get up
and down from the ground, squat body weight, and participate in a group exercise
regimen. The expertise of the Certified Strength and Conditioning Specialists to
progress or regress exercise choice based on movement patterns likely accounted for
the ability to train a broad range of skill levels with heavy weights and compound
movements. Future studies utilizing this method are underway and can further
elucidate these methods in more general cancer populations. Lastly, studies
assessing more experienced individuals may attempt to progress to full range of
motion in a shorter amount of time, which may produce greater strength and
hypertrophy gains.
Conclusion
Interim analysis of a dose-escalated resistance training exercise program in women
with breast cancer demonstrates favorable rates of safety and compliance while
showing significant improvements in body composition, balance, and strength. Future
exercise protocols in women with breast cancer should incorporate dose-escalated
resistance training and linear progression to achieve improvements in muscle mass,
fat mass, and functional capacity.
Bibliographical Record
Colin E. Champ, Chris Peluso, David J. Carenter, Jared Rosenberg, Frank Velasquez, Adam Annichine, Krista Matsko, Parker N. Hyde, Alexander K. Diaz, Sushil Beriwal, Christie Hilton. EXERT-BC: Prospective Study of an Exercise Regimen After Treatment
for Breast Cancer. Sports Med Int Open 2024; 08: a21930922.
DOI: 10.1055/a-2193-0922
