The authors would like to extend their thanks to the authors of the AMBER cohort study as well as everyone else who has and is currently involved in the AMBER study. To learn more about the AMBER cohort study and their baseline findings, visit their website https://www.amberstudy.com or scan this QR code:
Muscular strength, endurance, and body composition correlates of hand grip strength in newly diagnosed breast cancer patients post-surgery.
Matthew S. Steventon1, Spencer J. Allen1, Stephanie M. Ntoukas1, Fernanda Z. Arthuso1, Ki-Yong An1, & Kerry S. Courneya1.
1University of Alberta, Edmonton, AB, Canada.
Background
- In breast cancer patients, greater muscular strength is associated with increased physical function, decreased mortality, fewer side effects from treatment, and the completion of more chemotherapy.[1,2]
- Reduced lean body mass is similarly associated with decreased survival, quality of life, and treatment tolerance. [3]
- Given the above, there is considerable interest in measuring strength and body composition in breast cancer patients.
- However, multiple repetition maximum (mRM) muscular strength testing can be time-consuming, require expensive, specialized equipment, and can be challenging for patients who have recently undergone an upper-body surgery.
- Accurate assessment of body composition is similarly expensive and requires specialized equipment.
- Handgrip strength (HGS) assessment offers an alternative strength testing measure that is simple, inexpensive, and has been validated in the general population.
- However, little research has examined the relationship between HGS and muscular strength, endurance, or body composition in newly diagnosed breast cancer patients post-surgery.
Purpose
- The primary aim of this study was to examine the associations between HGS and other muscular strength and endurance measures in newly diagnosed breast cancer patients within 4-8 weeks of surgery.
- A secondary aim was to examine the associations between body composition and different measures of muscular strength and endurance
Hypothesis
- We hypothesize that HGS will correlate positively with measures of muscular strength, endurance, and lean mass, and that HGS will correlate better with measures of upper body strength compared to lower body strength.
Study Design and Participants
- Data for this cross-sectional analysis came from the Alberta Moving Beyond Breast Cancer (AMBER) cohort study. AMBER is an ongoing prospective cohort study examining how physical activity and health-related fitness variables are related to survival after breast cancer.
- Baseline musculoskeletal fitness and body composition data from 1528 female breast cancer survivors, recruited between 2012 and 2019, were collected at two cites (Edmonton and Calgary).
- Participants had newly diagnosed stage I (≥ T1c) to IIIc breast cancer and had completed surgery within 90 days. Their mean age was 56 ±11 years, with a mean BMI of 27.5 ±5.6.
Measures and Analysis
- Muscular strength and endurance measures were collected by exercise professionals following a standardized protocol.
- Body composition was assessed using full-body Dual-Energy X-ray Absorptiometry (DXA) scans.
- Using IBM SPSS 28 statistics software, a partial Pearson correlation analysis, controlling for age and BMI, was conducted to examine for correlations. Pairwise deletion was employed to manage missing data points.
For further details on the AMBER cohort
study and the methods of data collection,
scan this QR code with your phone’s camera.
Table 1. Correlation matrix presenting Pearson’s r correlation coefficients and p-values for correlations between measures of muscular strength, endurance, and body composition. df = Degrees of Freedom (N-2).
References
- An et al.(2021). Exercise and health-related fitness predictors of chemotherapy completion in breast cancer patients: Pooled analysis of two multicenter trials. Breast Cancer Research and Treatment, 188(2): 399–407.
- Klassen et al (2017). Muscle strength in breast cancer patients receiving different treatment regimes. Journal of Cachexia, Sarcopenia and Muscle, 8: 305–316.
- Mazzuca et al. (2018). Lean body mass wasting and toxicity in early breast cancer patients receiving anthracyclines. Oncotarget, 9(39): 25714-25722.
- Trosclair et al. (2011). Hand-grip strength as a predictor of muscular strength and endurance. Journal of Strength and Conditioning Research, 25: S99.
- Vaidya & Nariya. (2021). Handgrip strength as a predictor of muscular strength and endurance: A cross-sectional study. Journal of Clinical and Diagnostic Research, 15(1): YC01-YC04
Figure 1. Scatterplot for the correlation of handgrip strength and chest press predicted 1RM. N=1278, r=.45 (p<.001).
Figure 2. Scatterplot for the correlation of handgrip strength and absolute lean body mass. N=1445, r=.51 (p<.001).
HGS and Muscular Strength and Endurance
- In newly diagnosed breast cancer patients within 4-8 weeks of surgery, HGS appears to be a valid indicator of upper-body muscular strength but not muscular endurance.
- Given the relative weakness of the correlation with lower body muscular strength and abdominal strength, HGS may not be a useful tool for accurately predicting full-body muscular strength in this population.
- Due to the low cost, simplicity, and short time requirement to assess HGS compared to an mRM protocol, HGS may be a very useful tool for exercise professionals to assess upper body strength when working with breast cancer patients who have recently undergone surgery.
- Compared to previous research in the general population [4,5], HGS does not correlate as strongly with measures of muscular strength and endurance in breast cancer patients post-surgery.
HGS and Body Composition
- Body composition is associated with measures of muscular strength and endurance in breast cancer patients 4-8 weeks post-surgery.
- Lean mass had a stronger association with HGS than either chest or leg press predicted 1RMs.
Limitations and Future Research
- This study was correlational and can not establish any causal links between HGS, muscular strength and endurance, or body composition.
- Several study participants were unable to perform the mRM chest press protocol due to upper body pain as a result of surgery. It is unclear what effect this would have had on the strength of the correlation between HGS and chest press predicted 1RM.
- Further research should assess the impact of other factors such as surgery type, time since surgery, disease stage, and lymphedema on the associations between HGS and measures of musculoskeletal fitness and body composition in breast cancer survivors.