Limb Muscular Strength and Bone Mineral Density in Elderly Subjects with Low Skeletal Muscle Mass Index

Influence of two strength training modalities (hypertrophy vs. contrast training) on muscular strength, bone health parameters and quality of life in a group of older adults with low skeletal muscle mass index

The main aim of the current study was to compare the effects of two strength training modalities (hypertrophy vs. contrast training) on bone health parameters, physical performance and quality of life in a group of subjects aged 60 and above with low skeletal muscle mass index (SMI). 45 older adults voluntarily participated in this study, but only 41 (22 women and 19 men) completed it. The participants were assigned to 3 different groups: control group (CG; n = 15), contrast training group (CTG; n = 13) and hypertrophy training group (HTG; n = 13). The duration of the training protocol was six months. The experimental groups performed two sessions of strength training per week; the duration of each session was forty-five minutes. Several measurements (which included anthropometrics, body composition, bone parameters, maximal strength parameters, physical performance parameters, fracture risk and quality of life) were performed in the three groups before and after the six-month training period. The different measurements of the protocol were carried out under the same conditions with identical materials and investigators for all the participants and for each approach. The current study has demonstrated that the two training modalities show common benefits such as improving maximal strength, physical performance and quality of life parameters but have no significant effects on bone mineral density (BMD) and bone mineral content (BMC). The influence of training was marked more for improving maximal strength and reducing fracture risk for the contrast training group (who performs movements at high speed) compared to the hypertrophy training group (who performs movements at spontaneous speed). In conclusion, this study shows that both resistance training programs are effective in improving maximal strength, physical performance and quality of life in older adults with low SMI. However, this 6-month intervention was not sufficient to significantly increase BMC nor BMD values in this population.

Effects of Two Types of Resistance Training Modalities (Hypertrophy vs. Contrast Training) on Bone Parameters in a Group of Healthy Elderly Women

The aim of the present study was to explore the effects of two types of resistance training modalities (hypertrophy training vs. contrast training) on bone health parameters in a group of healthy elderly women. Forty-nine healthy elderly women whose ages range between 60 and 70 years were included in this study. The study population was randomly divided into three groups: hypertrophy training group (HTG; n=16), contrast training group (CTG; n=16) and control group (CG; n=17). Bone mineral density (BMD) values at the whole body (WB), lumbar spine (L1-L4), total hip (TH) and femoral neck (FN) were measured by DXA before and after 12 months of resistance training. Composite indices of femoral neck strength were calculated. WB BMD, L1-L4 BMD, TH BMD and FN BMD increased in the contrast training group. WB BMD and L1-L4 BMD increased in the hypertrophy training group, while TH BMD and FN BMD remained unchanged. Significant decreases in WB BMD, L1-L4 BMD, TH BMD and FN BMD were observed in the control group. The contrast training group showed the highest improvements in BMD values compared to the two other groups. Both experimental groups (HTG and CTG) showed similar significant improvements in composite indices of femoral neck strength and muscular strength. In conclusion, contrast training and hypertrophy training can stimulate bone gain at clinically important sites of osteoporotic fractures in elderly women.

Increased response of postmenopausal bone to interval walking training depends on baseline bone mineral density

PURPOSE

To examine the hypothesis that an increase in response of postmenopausal bone to interval walking training (IWT) depends on baseline bone mineral densities (BMDs).

METHODS

Two hundred and thirty-four postmenopausal women (64±5 (SD) yr) with no medication for osteoporosis performed 5-month IWT, repeating fast and slow walking at ≥70% and ~40% peak aerobic capacity, respectively, for 3 minutes each per set, ≥5 sets/day, ≥4 days/week. They were recruited from those who had performed IWT ≥6 months before participating in the study so that their physical fitness and lifestyle-related disease symptoms had almost reached a steady state at the time of their participation. We measured BMDs for the lumbar spine (LS), bilateral femoral neck (FN), and bilateral total hip (TH) by dual-energy X-ray absorptiometry (DXA) before and after the intervention. We used a multiple regression analysis to identify significant independent factors for increasing BMDs after the intervention as baseline physical characteristics, exercise intensity, and exercise time during IWT were the candidates. For any bone site where the independent factor identified was singular, we analyzed the relationship between the identified factor vs increases in BMD after the intervention (ΔBMD) by the locally weighted scatterplot smoothing (LOWESS) method.

RESULTS

Almost all subjects completed the designated protocol with minimal adverse events. We found that significant determinants for increasing BMDs were the baseline BMDs for all bone sites, as well as age and body mass index for TH (all, P<0.02). Furthermore, the LOWESS trendline between ΔBMDs vs the baseline BMDs, divided equally into 10 bins for LS and FN, respectively, showed that ΔBMD responses (Y) were attenuated as the baseline BMDs (X) increased in the lower 4 bins and then showed a flat line (Y = ~0) in the remaining higher 6 bins for LS and FN. When the lower 4 bins and the higher 6 bins of the baseline BMD were pooled, respectively, BMDs significantly increased by 1.8% and 1.0% in the lower groups for LS and FN, respectively (both, P<0.001) while not in the higher groups after the intervention (both, P>0.3).

CONCLUSIONS

IWT may be of benefit with minimal adverse events to postmenopausal women, although the effects were greater in those with lower baseline BMDs.

TRIAL REGISTRATION

UMIN000047428. https://rctportal.niph.go.jp/s/detail/um?trial_id=UMIN000047428#.

Correlation study between bone metabolic markers, bone mineral density, and sarcopenia

OBJECTIVE

To investigate the correlation between bone metabolism markers, bone mineral density (BMD), and sarcopenia.

METHODS

A total of 331 consecutive patients aged ≥ 60 years who were hospitalized between November 2020 and December 2021 were enrolled. Participants were divided into sarcopenia and non-sarcopenia groups according to the Asian Working Group on Sarcopenia criteria (AWGS, 2019). The clinical data, bone metabolism markers (β-CTX, N-MID, and TP1NP), and BMD were compared between the two groups.

RESULTS

Age, β-CTX, and N-MID of the sarcopenia group were higher than those of the non-sarcopenia group (P < 0.05), but the BMD T values were lower than those of the non-sarcopenia group (P < 0.05). Binary logistic regression analysis showed that increased femoral neck BMD (FNBMD) was a protective factor for sarcopenia, while increased β-CTX was a risk factor. Pearson/Spearman correlation analysis showed that the diagnostic indices of sarcopenia were positively correlated with FNBMD and negatively correlated with β-CTX and N-MID. Multiple linear regression analysis revealed that BMI and FNBMD significantly positively affected muscle strength and appendicular skeletal muscle mass (ASM). The FNBMD significantly positively affected physical performance, while β-CTX significantly negatively affected muscle strength, ASM, and physical performance.

CONCLUSION

Increased FNBMD may be a protective factor against sarcopenia, and increased β-CTX may be a risk factor. The FNBMD significantly positively affected the diagnostic indices of sarcopenia, while β-CTX significantly negatively affected them. BMD and bone metabolism marker levels may be considered in early screening for sarcopenia.

Analysis of related factors for sarco-osteoporosis in middle-aged and elderly inpatients and development and validation of a nomogram

BACKGROUND

Sarco-osteoporosis is a skeletal muscle disease associated with aging and complex pathological factors. At present, there are few studies on the analysis of its related factors, and a nomogram to estimate the risk of sarco-osteoporosis in middle-aged and elderly patients is not available.

METHODS

A total of 386 patients admitted to our hospital from October 2021 to October 2022 were collected, and the general demographic data and clinical data of the patients were collected.386 subjects were enrolled in the study and randomly divided into training set and validation set at a ratio of 7:3. In the training set, the Least absolute shrinkage and selection operator(LASSO)regression technique was used to select the optimal predictive features, and multivariate logistic regression was used to screen the factors associated with sarco-osteoporosis, and a nomogram was constructed using meaningful variables from multivariate analysis. The performance of the nomograms was assessed and validated by Area Under Curve (AUC) and calibration curves.

RESULTS

There were no significant differences in baseline characteristic of individuals in training set and validation set, six variables with non-zero coefficients were screened based on LASSO regression in the training set. Multivariate logistic regression analysis showed that the related factors for sarco-osteoporosis in middle-aged and elderly inpatients included age (OR = 1.08, 95%CI 1.03 ∼ 1.14), regular exercise (OR = 0.29, 95%CI 0.15 ∼ 0.56), albumin (OR = 0.9, 95%CI 0.82 ∼ 0.98), height (OR = 0.93, 95%CI 0.88 ∼ 0.99) and lean mass index (OR = 0.66, 95%CI 0.52 ∼ 0.85), and a nomogram was constructed based on the above factors. AUC of nomogram were 0.868(95%CI 0.825 ∼ 0.912) in the training set and 0.737(95%CI 0.646 ∼ 0.828) in the validation set. Calibration curve analysis showed that the predicted probability of sarco-osteoporosis had high consistency with the actual probability, and the absolute error of the training set and verification set was 0.018 and 0.03, respectively.

CONCLUSIONS

Our research showed that the occurrence of sarco-osteoporosis was associated with age, regular exercise, albumin, height and lean mass index, and we have developed a nomogram that can be effectively used in the preliminary and in-depth risk prediction of sarco-osteoporosis in middle-aged and elderly hospitalized patients.

Effects of Different Levels of Weightlifting Training on Bone Mineral Density in a Group of Adolescents

The aim of the current study was to evaluate the effects of different levels of weightlifting training on bone mineral density (BMD) at different body sites (whole body (WB), lumbar spine (LS), femoral neck (FN), upper limbs (UL) and lower limbs (LL)) in a group of adolescents. Three groups of pubertal boys aged 13-15 years were recruited, including a control group (which included 13 untrained adolescents), a moderately trained group (which included 13 non-elite weightlifters, with four sessions of 2 hours per week) and a highly trained group (which included 13 elite weightlifters, with eight sessions of 2 hours per week). The three groups were paired for age and maturation index (using Tanner stages). Body composition, bone mineral content (BMC) and BMD were evaluated by dual-energy X ray absorptiometry (DXA). Physical performance variables (including weightlifting specific exercises, counter movement jump and squat jump) were measured using validated methods. Results showed that the values of BMD and physical performance variables were greater in the group of elite weightlifters compared to the group of non-elite weightlifters and the control group. In addition, the values of BMD and physical performance variables were higher in the group of the non-elite weightlifters compared to those of the control group. After adjusting for lean mass and squat jump, lumbar spine BMD, FN BMD, UL BMD and LL BMD remained significantly higher in the elite weightlifters' group compared to the two other groups. In conclusion, the current study suggests that elite adolescent weightlifters have greater bone health parameters compared to moderately-trained adolescent weightlifters and untrained adolescents.