Impact of Body Composition Parameters on Lung Function in Athletes

Validity and agreement between dual-energy X-ray absorptiometry, anthropometry and bioelectrical impedance in the estimation of fat mass in young adults

Introduction

Assessment of fat mass has historically employed various methods like Dual-energy X-ray Absorptiometry (DXA), and bioelectrical impedance (BIA), and anthropometry with its set of formulas. However, doubts persist regarding their validity and interchangeability to evaluate fat mass. This research aimed to determine the validity of anthropometry, and BIA in estimating fat mass Vs DXA, considering the influence of sex and hydration status.

Methods

A descriptive, cross-sectional study included 265 young adults (161 males and 104 females), assessed through DXA, BIA in a standing position, and anthropometry. A fat mass estimation formula with DXA, a fat mass estimation formula with BIA and 10 fat mass estimation formulas with anthropometry were calculated.

Results

Significant differences were found across DXA, BIA and anthropometry in both kilograms and percentages for the overall sample (p<0.001), and when the covariable sex was included (p<0.001), with no significant effect of hydration status (p=0.332-0.527). Bonferroni-adjusted analyses revealed significant differences from DXA with anthropometry and BIA in most cases for the overall sample (p<0.001), as well as when stratified by sex (p<0.001-0.016). Lin's coefficient indicated poor agreement between most of the formulas and methods both in percentage and kilograms of fat mass (CCC=0.135-0.892). In the Bland-Altman analysis, using the DXA fat mass values as a reference, lack of agreement was found in the general sample (p<0.001-0.007), except for Carter's formula in kilograms (p=0.136) and percentage (p=0.929) and Forsyth for percentage (p=0.365). When separating the sample by sex, lack of agreement was found in males for all methods when compared with both percentage and kilograms calculated by DXA (p<0.001). In the female sample, all methods and formulas showed lack of agreement (p<0.001-0.020), except for Evans's in percentage (p=0.058).

Conclusion

The formulas for fat mass assessment with anthropometry and BIA may not be valid with respect to the values reported with DXA, with the exception of Carter's anthropometry formula for general sample and Evans's anthropometry formula for female sample. BIA could also be an alternative if what is needed is to assess fat mass in women as a group.

Associations of sarcopenia with peak expiratory flow among community-dwelling elderly population: based on the China Health and Retirement Longitudinal Study (CHARLS)

PURPOSE

To cross-sectionally and longitudinally investigate the correlations of sarcopenia and its components with peak expiratory flow (PEF) among Chinese community-dwelling elderly people.

METHODS

The data were extracted from the China Health and Retirement Longitudinal Study (CHARLS). A total of 4053 participants aged ≥ 60 years were enrolled from CHARLS 2011, and 2810 were followed up until 2015. Participants were classified into no-sarcopenia, non-severe sarcopenia, and severe sarcopenia groups based on skeletal muscle mass index (SMI), hand grip strength (HGS), and physical performance [gait speed, five-repetition chair stand test (5CST) and short physical performance battery (SPPB)]. Multivariate linear and logistic regression analyses were used to evaluate the associations of sarcopenia and its components with PEF cross-sectionally and longitudinally.

RESULTS

In the cross-sectional analysis, the prevalence of non-severe sarcopenia was 14.6% and severe sarcopenia was 4.9%. The results of linear regression analysis revealed that sarcopenia and its components were all correlated with PEF and PEF%pred. In the longitudinal analysis, compared with non-sarcopenia, subjects with severe sarcopenia were associated with a higher risk of PEF (OR = 2.05, 95%CI = 1.30-3.26) and PEF%pred (OR = 1.83, 95%CI = 1.17-2.86) decline. The changes in physical performance were correlated with changes in PEF and PEF%pred. No associations were observed between changes in SMI and PEF as well as PEF%pred.

CONCLUSIONS

We demonstrated the associations of baseline sarcopenia status with PEF and longitudinal PEF decline. Also, the changes in physical performance were associated with changes in PEF during a 4-year follow-up. It indicates that improving sarcopenia, especially physical performance may increase PEF.

Association of Muscle Fat Content and Muscle Mass With Impaired Lung Function in Young Adults With Obesity: Evaluation With MRI

RATIONALE AND OBJECTIVES

Although low muscle mass is associated with decreased lung function, studies exploring the relationship between muscle fat content and lung function impairment are scarce. This study aimed to evaluate the association of muscle mass and fatty infiltration with lung function in young adults with obesity.

MATERIALS AND METHODS

We performed a retrospective cross-sectional study of patients aged 18-45 years with obesity who had impaired pulmonary function (case group, n = 66) and those with normal pulmonary function (control group, n = 198) by matching age, sex, body mass index (BMI), and height to assess whether muscle characteristics differed. Muscle mass and muscle fat content were assessed by MRI using a chemical shift-encoded sequence (IDEAL-IQ).

RESULTS

A total of 264 patients were enrolled (124 females; mean age 32.0 years). The case group had lower muscle mass than the control group (p = 0.012), and there was an association between low muscle mass and lung function impairment (odds ratio (OR), 3.74; 95% confidence interval (CI), 1.57-8.93). Furthermore, muscle fat content was significantly higher in cases compared to controls (7.4 (2.7) % vs. 6.2 (2.5) %, p = 0.001). Multiple logistic regression analysis showed that muscle fat content was associated with a higher risk of impaired lung function (OR, 2.10; 95% CI, 1.65-2.66), regardless of adiposity and muscle mass.

CONCLUSION

Both muscle fat content and muscle mass are associated with impaired lung function in young adults with obesity.

Relationship between body composition and pulmonary function in the general population-a cross-sectional study in Ningxia

Studies considering the relationship between non-obesity-related body composition and lung function are few; therefore, this study aimed to explore these correlations and effects. This cross-sectional study conducted in rural Qingtongxia City and Pingluo County, Ningxia, China, included 776 participants aged 30-75 years. Body composition and lung function were measured using direct segmental multifrequency bioelectrical impedance analysis and a digital spirometer, respectively. Their correlation was assessed using partial correlation analysis, controlling for age and smoking status, and the body composition effect on lung function was analyzed using binomial logistic regression analysis. The body components total body water content, protein content, mineral content, muscle mass, fat-free mass (FFM), skeletal muscle mass, basal metabolic volume, and chest circumference (CC) positively correlated with pulmonary function (forced vital capacity and forced expiratory volume in one second) in both sexes. Neck circumference and hip circumference positively correlated with pulmonary function in women. Additionally, lung function declines more slowly in women (odds ratio [OR] = 0.66, 95% confidence interval [CI] = 0.44-0.98, p =  0.04); CC (OR = 0.92, 95% CI = 0.86-0.98, p = 0.01) increased as a protective factor for decreased lung function. Increased waist circumference (OR = 1.04, 95% CI = 1.00-1.09, p = 0.04) was a risk factor for reduced lung function. FFM contains body composition indicators positively correlating with lung function, excluding fat-related body composition. Abdominal obesity increases the risk of decreased lung function.

The role of body composition on cardio-respiratory fitness in futsal competitive athletes

Futsal is an intermittent high intensity sport which has become popular worldwide. Body composition and physical fitness have been studied in different sports disciplines. However, little is known regarding body composition and cardio-respiratory performance in competitive futsal players. Body composition parameters were analyzed by electrical impedance body composition analyzer in 31 competitive male futsal players. All participants performed spirometry, handgrip strength and cardiopulmonary exercise testing. Significant correlations were observed between muscle mass and spirometry parameters and peak VO2 (p≤0.05). Fat mass resulted inversely correlated with peak VO2% predicted and hand grip strength (p≤0.05). Regression analysis showed that muscle mass significantly predicts respiratory parameters (p<0.01) and reduced fat mass is associated with increased peak VO2 % predicted and handgrip strength (p<0.01). In futsal competitive athletes increased muscle mass is associated with higher spirometry parameters and fat mass is inversely associated with lower cardiorespiratory fitness.