Sarcopenic obesity is associated with impaired physical function and mortality in older patients with heart failure: insight from FRAGILE-HF

Sarcopenic Obesity and Cardiovascular Disease: An Overlooked but High-Risk Syndrome

PURPOSE OF REVIEW

Sarcopenic obesity (SO), defined as the coexistence of excess fat mass and reduced skeletal muscle mass and strength, has emerged as an important cardiovascular risk factor, particularly in older adults. This review summarizes recent findings on the diagnosis, prevalence, health impacts, and treatment of SO.

RECENT FINDINGS

Growing evidence suggests SO exacerbates cardiometabolic risk and adverse health outcomes beyond either condition alone; however, the heterogeneity in diagnostic criteria and the observational nature of most studies prohibit the evaluation of a causal relationship. This is concerning given that SO is increasing with the aging population, although that is also difficult to assess accurately given wide-ranging prevalence estimates. A recent consensus definition proposed by the European Society for Clinical Nutrition and Metabolism and the European Association for the Study of Obesity provides a framework of standardized criteria to diagnose SO. Adopting uniform diagnostic criteria for SO will enable more accurate characterization of prevalence and cardiometabolic risk moving forward. Although current management revolves around diet for weight loss coupled with resistance training to mitigate further muscle loss, emerging pharmacologic therapies have shown promising results. As the global population ages, diagnosing and managing SO will become imperative to alleviate the cardiovascular burden.

Detecting sarcopenia in obesity: emerging new approaches

PURPOSE OF REVIEW

Sarcopenic obesity is a likely common, but certainly underestimated obesity phenotype, with an important negative clinical impact. Its definition and diagnosis have however remained elusive until recently.

RECENT FINDINGS

Substantial progress has been recently made in sarcopenic obesity diagnostic tools, with the first international consensus proposed by the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO). Very encouraging results emerge from initial implementation of the ESPEN-EASO algorithm. In addition, even more recent progress in global consensus on sarcopenia conceptual definition is likely to further enhance consistency in sarcopenic obesity identification. The latter Global Leadership Initiative on Sarcopenia (GLIS) initiative also adopted a new definition of muscle specific strength. Its inclusion in sarcopenia diagnostic constructs opens the possibility of its potential evaluation in sarcopenic obesity, also considering the emerging positive impact of obesity treatment and fat loss on muscle functional parameters.

SUMMARY

New consensus tools for sarcopenic obesity diagnosis are likely to improve awareness, understanding, identification and treatment of this under-recognized obesity phenotype.

Association between systemic immune-inflammation index and sarcopenic obesity in middle-aged and elderly Chinese adults: a cross-sectional study and mediation analysis

BACKGROUND

Despite the known association between chronic inflammation and reduced muscle mass, there is a gap in research regarding the association between the systemic immune-inflammation index (SII) and sarcopenic obesity (SO). This study aims to assess the relationship between SII and SO in middle-aged and elderly adults and the mediating role of triglyceride-glucose index (TyG).

METHODS

This cross-sectional study involved 2,719 participants aged 45-90 years who underwent health check-ups. SO was evaluated by combining sarcopenia [assessed by handgrip strength and appendicular skeletal muscle index (ASMI)] with obesity (determined by body fat percentage). Association between SII and SO, sarcopenia, and obesity in middle-aged and elderly individuals was examined using multivariable logistic regression, restricted cubic spline analysis, and subgroup analysis. Bidirectional mediation analysis was conducted to determine the direct and indirect effects through SII and TyG.

RESULTS

The study included 2,719 participants, of which 228 had SO (8.4%). SO prevalence increased as the SII quartiles rose (Pfor trend <0.001). SII (per SD increase) had a significantly positive association with SO in both middle-aged individuals (OR = 1.69, 95% CI: 1.43 ~ 1.99) and older adults (OR = 2.52, 95% CI: 1.68 ~ 3.77). The relationship between SII and SO was found to be non-linear (Pnonlinear<0.05). In addition, SII showed a strong negative relationship with both handgrip strength and ASMI across all participants. In subgroup analysis, SII was still shown to significantly increase the risk of SO in all subgroups by gender, body mass index, waist circumference, smoking, drinking, hypertension, diabetes, dyslipidemia. TyG was found to mediate 21.36%, 11.78%, and 9.94% of the associations between SII and SO, sarcopenia, and obesity, respectively. SII had no mediation effect on the association between TyG and SO, sarcopenia, and obesity (P>0.05).

CONCLUSIONS

Elevated levels of SII were associated with an increased risk of SO in middle-aged and elderly adults, especially in the elderly population, and elevated TyG levels played a role in this relationship.

Ct-based diagnosis of sarcopenia as a prognostic factor for postoperative mortality after elective open-heart surgery in older patients: a cohort-based systematic review and meta-analysis

Background

Cardiac open-heart surgery, which usually involves thoracotomy and cardiopulmonary bypass, is associated with a high incidence of postoperative mortality and adverse events. In recent years, sarcopenia, as a common condition in older patients, has been associated with an increased incidence of adverse prognosis.

Methods

We conducted a search of databases including PubMed, Embase, and Cochrane, with the search date up to January 1, 2024, to identify all studies related to elective cardiac open-heart surgery in older patients. We used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to assess the certainty of evidence.

Results

A total of 12 cohort studies were included in this meta-analysis for analysis. This meta-analysis revealed that patients with sarcopenia had a higher risk of postoperative mortality. Furthermore, the total length of hospital stay and ICU stay were longer after surgery. Moreover, there was a higher number of patients requiring further healthcare after discharge. Regarding postoperative complications, sarcopenia patients had an increased risk of developing renal failure and stroke.

Conclusion

Sarcopenia served as a tool to identify high-risk older patients undergoing elective cardiac open-heart surgery. By identifying this risk factor early on, healthcare professionals took targeted steps to improve perioperative function and made informed clinical decisions.Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023426026.

Sarcopenic obesity and falls in older adults: A validation study of ESPEN/EASO criteria and modifications in Western China communities

OBJECTIVES

The ESPEN and the EASO recently developed consensus criteria for sarcopenic obesity (SO), employing the skeletal muscle mass to weight (SMM/W) ratio. Emerging evidence suggests that adjusting skeletal muscle mass for body mass index (SMM/BMI) could enhance the predictive accuracy for health outcomes. We aimed to validate the ESPEN/EASO criteria and explore the potential benefits of the SMM/BMI adjustment in predicting falls among older adults in Western China.

METHODS

We conducted a multicenter, cross-sectional study and included community-dwelling older adults. The diagnosis of SO was determined using the standard ESPEN/EASO consensus criteria (SOESPEN) and a modified version adjusting SMM/BMI (SOESPEN-M). The associations of SOESPEN, SOESPEN-M, and their components with falls were analyzed.

RESULTS

Among the 1353 participants, the prevalence of SO was 13.2 % (SOESPEN) and 11.4 % (SOESPEN-M), which increased with age and higher BMI levels. Within participants with a normal BMI, 4.2 % and 6.2 % were found to have SOESPEN and SOESPEN-M, respectively. SMM/W and SMM/BMI negatively correlated with fall risk (p=0.042 and p=0.021, respectively). Upon adjusting for confounders, only SOESPEN was significantly associated with falls (odds ratios [OR] 1.61, 95 % confidence interval [CI] 1.08 to 2.40), whereas the association for SOESPEN-M did not achieve significance (OR 1.55, 95 % CI 0.99 to 2.43).

CONCLUSIONS

This research validated the ESPEN/EASO criteria (SOESPEN) and their modified version (SOESPEN-M) among community-dwelling older adults in Western China. The SMM/BMI adjustment appears to offer a lower estimate of SO prevalence, with only SOESPEN showing a significant association with falls.

ALM/BMI: A Clinically Superior Index for Identifying Skeletal Muscle Dysfunction in Patients With Heart Failure

BACKGROUND

Skeletal muscle wasting is critical in patients with heart failure (HF). Whereas prior studies have employed appendicular lean mass (ALM) normalized by height squared to identify low skeletal muscle mass, the potential of ALM normalized to body mass index (ALM/BMI) remains unexplored in patients with HF. In this study, we compared the use of 2 skeletal muscle mass indices in patients with HF to examine their sex-specific correlations with measures of physical capacity, quality of life, and daily physical activity.

METHODS AND RESULTS

A total of 111 patients with HF underwent dual x-ray absorptiometry, physical capacity tests, and accelerometry and answered a quality-of-life questionnaire. ALM normalized by height squared and ALM/BMI indices disagreed in classifying low muscle mass (Cohen's κ, -0.008 [95% CI, -0.094 to 0.177]; P=0.93). ALM/BMI correlated well with 6-minute walking distance in women and men (R=0.67 and 0.49; P<0.001), with maximal oxygen uptake in women and men (R=0.41 and 0.48; P<0.05), and with maximal muscle strength in women and men (R=0.54 and 0.43; P<0.01). Inversely, ALM normalized by height squared did not correlate significantly with 6-minute walking distance or maximal oxygen uptake and correlated with maximal muscle strength only in men (R=0.43; P<0.001). Only ALM/BMI allowed for identification of a low-muscle-mass group characterized by poor quality of life (Minnesota Living With Heart Failure Questionnaire score of 33±21 versus 25±16; P=0.027) and less daily time spent in moderate to vigorous physical activity (8 [3-17] versus 15 [9-37] minutes; P<0.001).

CONCLUSIONS

ALM/BMI was superior for identifying clinically significant muscle dysfunction in both female and male patients with HF.

Sarcopenic obesity in older adults: a clinical overview

Sarcopenic obesity is characterized by a concurrent decline in muscle mass and function, along with increased adipose tissue. Sarcopenic obesity is a growing concern in older adults owing to significant health consequences, including implications for mortality, comorbidities and risk of developing geriatric syndromes. A 2022 consensus statement established a new definition and diagnostic criteria for sarcopenic obesity. The pathophysiology of this condition involves a complex interplay between muscle, adipose tissue, hormonal changes, inflammation, oxidative stress and lifestyle factors, among others. Sarcopenic obesity is treated with a range of management approaches, such as lifestyle interventions, exercise, nutrition and medical therapies. Emerging therapies that were developed for treating other conditions may be relevant to sarcopenic obesity, including novel pharmacological agents and personalized approaches such as precision medicine. In this Review, we synthesize the current knowledge of the clinical importance of sarcopenic obesity, its assessment and diagnosis, along with current and emerging management strategies.

Sarcopenia is linked to higher levels of B-type natriuretic peptide and its N-terminal fragment in heart failure: a systematic review and meta-analysis

AIMS

Sarcopenia is linked to impaired physical function and exercise tolerance. The aim of this systematic review and meta-analysis was to examine the association of sarcopenia and low appendicular skeletal muscle (ASM) with biomarkers of cardiac function, B-type natriuretic peptide (BNP) and its N-terminal fragment (NT-proBNP), in patients with heart failure (HF).

METHODS AND RESULTS

From inception until May 2023, a systematic literature search of observational studies was undertaken utilizing the PubMed, Web of Science, Scopus, and Cochrane Library databases. A meta-analysis employing a random-effects model was used to compute the pooled effects (CRD42023418465). Overall, 16 studies were included in this systematic review and meta-analysis. Our main analysis showed that sarcopenia in HF was linked to significantly higher levels of BNP (MD: 87.76, 95% CI 20.74-154.78, I2 = 61%, P = 0.01) and NT-proBNP (MD: 947.45, 95% CI 98.97-1795.93, I2 = 35%, P = 0.03). Similarly, low ASM was associated with significantly higher levels of BNP (MD: 118.95, 95% CI 46.91-191.00, I2 = 93%, P < 0.01) and NT-proBNP (MD: 672.01, 95% CI 383.72-960.30, I2 = 2%, P < 0.01). The quality of the included cohort studies was considered moderate, using the binary AXIS checklist and the Cochrane Tool to Assess the Risk of Bias in Cohort Studies.

CONCLUSIONS

In patients with HF, sarcopenia and reduced ASM are associated with considerably higher plasma levels of BNP and NT-proBNP. Future research is required to investigate whether sarcopenia may express dysregulated biomarkers of cardiac function.

Sarcopenic obesity does not impair lower limb strength and physical performance in sufficiently active older adults: a cross-sectional study

This study investigated the associations of sarcopenic obesity (SO) with muscle strength and physical performance in sufficiently active older adults. Data from 72 older sarcopenic obese adults classified as sufficiently active were analyzed. Participants were categorized into four groups based on sex and SO status. Muscle strength/physical performance tests were compared using independent sample t-tests. Multiple linear regression and binary logistic regression were performed to examine the associations between SO and muscle strength and physical performance, adjusting for confounding variables. Only handgrip strength showed differences between SO groups, regardless of sex (p < 0.05). SO negatively explained the variability of handgrip strength (p < 0.05). An increase in handgrip strength values was associated with a decrease in the chances of older adults being classified as SO (p < 0.05). The findings suggest that even with SO, sufficiently active older adults did not present a significant reduction in muscle strength in the lower limbs and physical performance.

The Safety and Efficacy of Sodium-Glucose Cotransporter-2 Inhibitors for Patients with Sarcopenia or Frailty: Double Edged Sword?

Sodium-glucose cotransporter-2 inhibitors (SGLT-2is) show cardiovascular protective effects, regardless of the patient's history of diabetes mellitus (DM). SGLT2is suppressed cardiovascular adverse events in patients with type 2 DM, and furthermore, SGLT-2is reduced the risk of worsening heart failure (HF) events or cardiovascular death in patients with HF. Along with these research findings, SGLT-2is are recommended for patients with HF in the latest guidelines. Despite these benefits, the concern surrounding the increasing risk of body weight loss and other adverse events has not yet been resolved, especially for patients with sarcopenia or frailty. The DAPA-HF and DELIVER trials consistently showed the efficacy and safety of SGLT-2i for HF patients with frailty. However, the Rockwood frailty index that derived from a cumulative deficit model was employed for frailty assessment in these trials, which might not be suitable for the evaluation of physical frailty or sarcopenia alone. There is no fixed consensus on which evaluation tool to use or its cutoff value for the diagnosis and assessment of frailty in HF patients, or which patients can receive SGLT-2i safely. In this review, we summarize the methodology of frailty assessment and discuss the efficacy and safety of SGLT-2i for HF patients with sarcopenia or frailty.

Is sarcopenia an associated factor of increased administration of specific medications in patients with heart failure? A systematic review and meta-analysis

Background

There is controversy in relation to commonly used drugs in heart failure (HF) and their impact on muscle function. The aim of this study was to evaluate the odds of receiving specific medications often used in clinical practice by patients with HF and sarcopenia vs. without sarcopenia.

Methods

A systematic literature search of cohort studies via databases (PubMed, Web of Science, Scopus, and Cochrane Library) was conducted from inception until March 2023. To determine if sarcopenia is linked to a higher number of specific HF-related medications, a meta-analysis using a random-effects model was used to calculate the pooled effects.

Results

Our main analyses showed no significant association of sarcopenia with administration of higher HF-related medication count vs. those without sarcopenia. Those with lower appendicular lean mass (ALM) had significantly lower odds of receiving angiotensin converting enzyme inhibitors (ACE-Is)/angiotensin receptor blockers (ARBs) (OR: 0.68, 95%CI 0.50-0.90, I2 = 12%, P < 0.01) vs. patients with higher ALM for which age could be an important confounder based on meta-regression. No statistically significant differences were found in relation to B-blockers OR: 0.84, 95%CI 0.63-1.12, I2 = 7%, P = 0.24) and loop diuretics (OR: 1.19, 95%CI 0.87-1.63, I2 = 0%, P = 0.27). Regarding handgrip strength, gait speed, and short physical performance battery, our narrative synthesis found mixed results.

Conclusion

This systematic review and meta-analysis did not find a relationship of specific medication count in sarcopenia vs. without sarcopenia in patients with HF, although increased odds of ACE-I/ARB was shown in those with higher ALM.

Systematic Review Registration

PROSPERO (CRD42023411137).

Obesity paradox in older sarcopenic adults - a delay in aging: A systematic review and meta-analysis

The prognostic significance of obesity in sarcopenic adults is controversial. This systematic review and meta-analysis aimed to investigate the effect of additional obesity on health outcomes in sarcopenia. MEDLINE, EMBASE, Scopus and CENTRAL were systematically searched for studies to compare health outcomes of adults with sarcopenic obesity (SO) to those of sarcopenic non-obese (SNO) adults. We also considered the methods of assessing obesity. Of 15060 records screened, 65 papers were included (100612 participants). Older community-dwelling SO adults had 15% lower mortality risk than the SNO group (hazard ratio, HR: 0.85, 95% confidence interval 0.76, 0.94) even when obesity was assessed by measurement of body composition. Additionally, meta-regression analysis revealed a significant negative linear correlation between the age and the HR of all-cause mortality in SO vs. SNO community-dwelling adults, but not in severely ill patients. Compared with SNO, SO patients presented lower physical performance, higher risk for metabolic syndrome, but similar cognitive function, risk of falls and cardiovascular diseases. Age-related obesity, SO and later fat loss leading to SNO represent consecutive phases of biological aging. Additional obesity could worsen the health state in sarcopenia, but above 65 years SO represents a biologically earlier phase with longer life expectancy than SNO.

Bioelectrical Impedance Analysis and Body Composition in Cardiovascular Diseases

Nutritional status and body composition in cardiovascular (CV) patients are important aspects of their performance. Bioelectrical impedance analysis (BIA) is a noninvasive method that provides reliable information about bioelectrical parameters which reflect nutritional status and body composition data. The aim of this paper was to describe BIA, its advantages, limitations, and clinical applications in CV patients. The PubMed database was searched for all papers showing the use of BIA in CV conditions until January 1, 2023. A total of 42 papers regarding BIA application in CV patients were identified. Phase angle, Z200/5 parameter, and membrane capacitance are the BIA parameters that can be used for nutritional status assessment in CV patients, mainly in heart failure and after myocardial infarction. Among secondary body composition parameters, fat mass can be used for obesity assessment which is a CV risk factor. Body cell mass can be used together which the direct BIA parameters for nutritional status assessment which is an important factor in treatment outcome, quality of life, and disease prognosis. Total body water can be used for hydration assessment in heart failure and during invasive procedures. To conclude, BIA is a noninvasive method that provides essential information about the general condition of the body which is the result of nutritional and hydration status in CV patients.

Obesity phenotypes and cardiovascular risk: From pathophysiology to clinical management

Obesity epidemic reached the dimensions of a real global health crisis with more than one billion people worldwide living with obesity. Multiple obesity-related mechanisms cause structural, functional, humoral, and hemodynamic alterations with cardiovascular (CV) deleterious effects. A correct assessment of the cardiovascular risk in people with obesity is critical for reducing mortality and preserving quality of life. The correct identification of the obesity status remains difficult as recent evidence suggest that different phenotypes of obesity exist, each one associated with different degrees of CV risk. Diagnosis of obesity cannot depend only on anthropometric parameters but should include a precise assessment of the metabolic status. Recently, the World Heart Federation and World Obesity Federation provided an action plan for management of obesity-related CV risk and mortality, stressing for the instauration of comprehensive structured programs encompassing multidisciplinary teams. In this review we aim at providing an updated summary regarding the different obesity phenotypes, their specific effects on CV risk and differences in clinical management.

Assessing quality of life with SarQol is useful in screening for sarcopenia and sarcopenic obesity in older women

BACKGROUND

Health-related quality of life (HRQoL) may be impaired in the presence of sarcopenia. Since a specific quality of life questionnaire became available for sarcopenia (SarQol), cutoffs to screen for this condition have been proposed, prompting the need to assess them in different populations. Due to the lack of consensus on diagnostic criteria, the tool has not yet been analyzed in screening for sarcopenic obesity.

AIM

Our aim is to measure the SarQoL's metric properties and establish a cutoff in QoL assessments that could be used along the diagnostic pathway for sarcopenia and sarcopenic obesity in community-dwelling older women.

METHODS

This cross-sectional study assessed women aged ≥ 70 years using the SarQol, sarcopenia criteria (EWGSOP2) and sarcopenic obesity criteria (ESPEN/EASO). Cutoffs for the SarQol were defined with a receiver-operating characteristics (ROC) curve, and sensitivity and specificity were analyzed.

RESULTS

Of the 95 included women (mean age 76.0 years, standard deviation [SD] 5.7), 7.3% (n = 7) were classified as having sarcopenic obesity, 22.1% (n = 21) as having sarcopenia, and 70.5% (n = 67) as not having sarcopenia. The total SarQol score was higher in women without sarcopenia (66.5 SD 16.2) versus those with sarcopenia (56.6 SD 15.6) and sarcopenic obesity (45.1 SD 7.9). A cutoff of ≤ 60 points is proposed for sarcopenia screening (area under the ROC curve [AUC] 0.67; 95% confidence interval [CI] 0.53-0.80; sensitivity 61.9%; specificity 62%), and ≤ 50 points for sarcopenic obesity (AUC 0.85; 95% CI 0.74-0.95; sensitivity 71.4%; specificity 76.9%).

CONCLUSIONS

Quality of life is compromised in women with sarcopenia and especially in those with sarcopenic obesity. The SarQol could be useful in screening for these conditions, providing insight into health-related quality of life in older people with sarcopenia.

Understanding the development of sarcopenic obesity

INTRODUCTION

Sarcopenic obesity (SarcO) is defined as the confluence of reduced muscle mass and function and excess body fat. The scientific community is increasingly recognizing this syndrome, which affects a subgroup of persons across their lifespans and places them at synergistically higher risk of significant medical comorbidity and disability than either sarcopenia or obesity alone. Joint efforts in clinical and research settings are imperative to better understand this syndrome and drive the development of urgently needed future interventions.

AREAS COVERED

Herein, we describe the ongoing challenges in defining sarcopenic obesity and the current state of the science regarding its epidemiology and relationship with adverse events. The field has demonstrated an emergence of data over the past decade which we will summarize in this article. While the etiology of sarcopenic obesity is complex, we present data on the underlying pathophysiological mechanisms that are hypothesized to promote its development, including age-related changes in body composition, hormonal changes, chronic inflammation, and genetic predisposition.

EXPERT OPINION

We describe emerging areas of future research that will likely be needed to advance this nascent field, including changes in clinical infrastructure, an enhanced understanding of the lifecourse, and potential treatments.

Effects of non-pharmacological interventions on patients with sarcopenic obesity: A meta-analysis

OBJECTIVE

Systematic evaluation of the improvement effect of non-pharmacological intervention on patients with sarcopenic obesity.

METHODS

Wanfang, VIP, China National Knowledge Infrastructure (CNKI), SinoMed, Web of Science, Cochrane Library, PubMed, and Embase databases were searched systematically for randomized controlled trials (RCTS) and experimental studies of non-pharmacological interventions on patients with sarcopenic obesity. The retrieval period was from the establishment of the databases to October 31, 2022. Meta-analysis was conducted using RevMan 5.4.

RESULTS

A total of 18 studies involving 1,109 patients were included. Meta-analysis results showed that non-pharmacological interventions improved patients' body weight [mean difference, MD = -2.74, 95% CI (-4.79, -0.70), P = 0.009], body fat percentage [MD = -0.67, 95% CI (-0.96, -0.38), P<0.00001], grip strength [MD = 1.29, 95% CI (0.81, 1.77), P<0.00001], gait speed [MD = 0.05, 95% CI (0.03, 0.07), P<0.00001], and knee extension strength [MD = 2.56, 95% CI (1.30, 3.82), P<0.0001].

CONCLUSIONS

Non-pharmacological interventions can effectively improve the clinical symptoms and signs of patients with sarcopenic obesity. Dissemination of this information will be therapeutically useful.

TRIAL REGISTRATION

Registration. The PROSPERO No. is CRD42023403341.

Characteristics of resistance training-based protocols in older adults with sarcopenic obesity: a scoping review of training procedure recommendations

Background

Sarcopenic obesity (SO) is a clinical and functional disease characterized by the coexistence of obesity and sarcopenia. Resistance training (RT) characteristics for older adults with sarcopenia or obesity are already well established in the scientific literature. Nonetheless, we still do not know how detailed the RT protocols are described for older adults with SO. Therefore, we aimed to analyze the characteristics of RT programs, including each of their variables, recommended for older adults with SO.

Methods

This is a scoping review study that was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews. The search was carried out until November 2022 in PubMed/MEDLINE, EMBASE, Cochrane Library, Web of Science, Scopus, LILACS, Google Scholar, and medRxiv databases. The studies included SO diagnosis and RT as an intervention strategy. The RT variables analyzed were as follows: exercise selection, the volume of sets, the intensity of load, repetition cadence, rest interval between sets, and weekly frequency.

Results

A total of 1,693 studies were identified. After applying the exclusion criteria, 15 studies were included in the final analysis. The duration of the RT intervention ranged from 8 to 24 weeks. All studies included full-body routines, with single/multi-joint exercises. Regarding the volume of sets, some studies fixed it in three sets, whereas others varied between one and three sets. The load was reported by repetition range and the weight lifted, elastic-band color/resistance, percentage of one repetition maximum, or perceived exertion scale. Repetition cadence was fixed in some studies, while it was self-selected between concentric and eccentric phases in others. The interval between sets of rest varied from 30 to 180 s. All studies reported progression overload during the interventions. Not all studies reported how the exercise selection, repetition cadence, and rest interval were made.

Conclusion

The characteristics of RT protocols and their variables prescribed in the literature for older adults with SO were mapped. The lack of detail on some training variables (i.e., exercise selection, repetition cadence, and rest interval) was identified. RT protocols are heterogeneous and described only partially among studies. The recommendations for RT prescription details in older adults with SO are provided for future studies.

Systematic review registration

https://osf.io/wzk3d/.