The masseter muscle can be evaluated in various ways to examine its condition in healthy individuals or to identify pathological changes in the muscle. This study aimed to examine the tone and viscoelastic parameters of the masseter muscle, which is the focal muscle of various pathologies, to reveal its relationship with age and gender, and to determine the reference values of this muscle in healthy individuals. Individuals aged 18-50 years were evaluated. They were divided into 3 groups in terms of age. A total of 389 individuals participated in the study (18-28 years: 131 males, 104 females; 29-39 years: 29 males, 56 females; and 40-50 years: 30 males, 39 females). The tone and viscoelastic properties of the masseter muscle were evaluated bilaterally in the supine position. The mean age of all individuals was 28.64 ±9.68 years. The masseter muscle tone was found to be higher in men than in women. The elasticity of the muscle was higher in women (p < 0.05). It was determined that the masseter muscle tone and stiffness increased, whilst its elasticity decreased with aging (p < 0.05). A weak positive correlation was found between the right and left masseter muscle tone and age (r = 0.307 and r = 0.325, respectively; p = 0.001). There was a moderate positive correlation between the right and left masseter muscle stiffness and age (r = 0.507 and r = 0.511, respectively; p = 0.001). A strong positive correlation was observed between the right and left masseter muscle elasticity and age (r = 0.614 and r = 0.645, respectively; p = 0.001). The data obtained in this study may assist clinicians in evaluating the treatment of the pathological conditions related to the masseter muscle as well as in the planning of treatment and preand post-operation evaluations. Cite as.

Background: The body mass index (BMI) is closely related to fat tissue, which may have direct or indirect effects on muscle function. Previous studies have evaluated BMI and muscle viscoelastic properties in vivo in older people or individual sexes; however, the relationship between BMI and muscular viscoelastic properties is still unknown. Aims: The purpose of this study was to determine the correlation of BMI with muscular viscoelastic properties, and to compare these properties in a young sedentary population with normal and overweight individuals. Methods: A total of 172 healthy sedentary individuals (mean age, 26.00 ± 5.45 years) were categorized by sex (male and female) and BMI classification (normal (BMI, 18.50–24.99 kg/m²), overweight (BMI = 25.00–29.99 kg/m²)). Body weight was evaluated using an electronic scale, while height was measured using a standard stadiometer. BMI was calculated by dividing the weight in kilograms by the square of height in meters. The viscoelastic properties (tone, stiffness, and elasticity) of the biceps brachii (BB) and biceps femoris (BF) muscles were measured bilaterally using the MyotonPRO device at rest. Results: The bilateral BF tone and stiffness, right BB stiffness, and elasticity showed weak correlations with BMI in all participants. Furthermore, the bilateral BF tone and stiffness, right BB stiffness and elasticity, and left BB stiffness were weakly positively correlated with male sex. Only the right BB elasticity was weakly positively correlated with BMI in females (p < 0.05). No correlation with BMI was determined for other viscoelastic properties (p > 0.05). The overweight group showed increased bilateral BF stiffness and tone, right BB stiffness, and reduced bilateral BB elasticity compared to the normal-weight group (p < 0.05), while other viscoelastic properties were similar (p > 0.05). Greater bilateral BB tone, BF tone and stiffness, and lower BF elasticity were observed in males than in females (p < 0.05), but other viscoelastic properties were not significantly different (p < 0.05). No effect of BMI–sex interactions was found on viscoelastic properties (p > 0.05). Conclusions: The BB and BF viscoelastic properties were weakly correlated with BMI. Males showed greater muscle tone and stiffness, and lower elasticity. The overweight individuals showed increased stiffness and tone, particularly in lower extremities, and reduced elasticity in upper extremities. The effect of BMI–sex interactions on the viscoelastic properties was not clear. Higher BMI (increased mechanical load) might cause the human body to develop different muscular viscoelastic adaptations in the extremities.

Introduction: This study aimed to establish normative values for stiffness, tone, and elasticity of lower extremity muscles and to determine age and sex differences.Methods: Overall, 389 participants (199 females, 190 males) were included. The mechanical properties of the tibialis anterior (TA), rectus femoris (RF), vastus lateralis (VL), vastus medialis obliquus (VMO), gastrocnemius lateralis (GL), and gastrocnemius medialis (GM) muscles were assessed bilaterally with the MyotonPRO device. The data were compared with respect to sex and age.Results: The mechanical properties were significantly higher bilaterally in males than females in all parameters (p < 0.05). Right TA stiffness and elasticity, GM tone and stiffness were higher than left in females (p < 0.05). Greater VMO elasticity and RF tone were found in left vs. right (p < 0.05). Right GL-VL stiffness and elasticity were greater than left in males (p < 0.05). VMO-RF tones were bigger in left compared with right (p < 0.05). Among age groups, right-left TA tone and stiffness were greater in group 1 (18–28 years old) (p < 0.05). Right-left VL-VMO tones, and left RF stiffness and tone were lower in group 2 (29–39 years old) (p < 0.05). Right GM-VMO stiffness, right-left TA-GL-GM-VMO and RF elasticity were greater in group 3 (40–50 years old) compared with others (p < 0.05).Conclusions: The mechanical properties of leg muscles were bilaterally higher in males. Different characteristics were observed of different muscles for both sexes. GL-GM-VMO-RF elasticity decreased, and TA stiffness and VMO tone increased with advancing age in both legs

Background: The study was to determine the relation of body mass index to muscular mechanical properties in normal and overweight individuals Methods: A total of 172 participants (86 males and 86 females, mean age; 26.00±5.45 years) were participated. The participants were assigned in groups base on BMI classification (normal (BMI=18.50-24.99 kg/m²), overweight (BMI=25.00-29.99 kg/m²). The biceps brachii (BB), biceps femoris (BF) were measured bilaterally using the "MyotonPRO" device. Results: Bilateral BB and BF stiffness, and BB elasticity were found significantly difference between normal and overweight group (p<0.05). Also the only left BB tone was found different (p0.05). In sex based BMI sub-categories comprasion; the bilaterally BB and BF stiffness and BF tone were found higher, and only the right BB elasticity was decreased in overweight male group (p<0.05). While the other mechanical parameters were found similar (p<0.05). The right BB stiffness and elasticity were found higher in overweight female group (p0.05).A weak positive correlation was found between the right-left BB tone and stiffness and BMI. Also, a weak positive correlation was revealed between the right BB elasticity (p0.05).Conclusions: The bilateral BB and BF stiffness increased and BB elasticity decreased as BMI increased. The BB and BF mechanical properties were affected more in males than females when BMI considered.

Amaç: Bu çalışma farklı kanser türüne sahip bireyler ile bakım verenlerinde fiziksel aktivite, yorgunluk ve yaşam kalitesinin incelenmesi amacıyla yapıldı. Gereç ve Yöntemler: Çalışmaya akciğer kanseri (n=60, yaş: 55.77±7.27 yıl, Vücut Kütle İndeksi-VKİ; 20.22±1.12 kg/m2), meme kanseri (n=60, yaş:49.68±9.51 yıl, VKİ: 20.72±1.18 kg/m2) ve kolon kanseri (n=60, yaş: 52.53±7.77 yıl, VKİ: 19.57±0.92 kg/m2) olmak üzere 180 kanser hastası ve 180 bakım vereni dahil edildi. Fiziksel aktivite düzeyi Uluslararası Fiziksel Aktivite Anketi (IPAQ) ile, yorgunluk ise Piper Yorgunluk Ölçeği ile değerlendirildi. Yaşam kalitesi kanser hastalarında EORTC-QLQ-30, bakım verenlerde ise SF-36 yaşam kalitesi ölçeği ile değerlendirildi. Bulgular: Yorgunluk akciğer kanseri ve bakım verenlerinde yüksek, meme kanseri ve bakım verenlerinde düşüktü (p