Skeletal muscle mass and distribution in 468 men and women aged 18–88 yr

2000 ◽  
Vol 89 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Ian Janssen ◽  
Steven B. Heymsfield ◽  
ZiMian Wang ◽  
Robert Ross
Keyword(s):  
Skeletal Muscle ◽  
Gender Differences ◽  
Body Weight ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body ◽  
Large Measure ◽  
Imaging Protocol ◽  
Men And Women ◽  
Magnetic Resonance Imaging Protocol

We employed a whole body magnetic resonance imaging protocol to examine the influence of age, gender, body weight, and height on skeletal muscle (SM) mass and distribution in a large and heterogeneous sample of 468 men and women. Men had significantly ( P < 0.001) more SM in comparison to women in both absolute terms (33.0 vs. 21.0 kg) and relative to body mass (38.4 vs. 30.6%). The gender differences were greater in the upper (40%) than lower (33%) body ( P < 0.01). We observed a reduction in relative SM mass starting in the third decade; however, a noticeable decrease in absolute SM mass was not observed until the end of the fifth decade. This decrease was primarily attributed to a decrease in lower body SM. Weight and height explained ∼50% of the variance in SM mass in men and women. Although a linear relationship existed between SM and height, the relationship between SM and body weight was curvilinear because the contribution of SM to weight gain decreased with increasing body weight. These findings indicate that men have more SM than women and that these gender differences are greater in the upper body. Independent of gender, aging is associated with a decrease in SM mass that is explained, in large measure, by a decrease in lower body SM occurring after the fifth decade.

Recognition and prediction of driver’s whole body posture model

2022 ◽  
pp. 095440702110686
Author(s):  
Jun Wu ◽  
Jian Liu ◽  
Xiuyuan Li ◽  
Lingbo Yan ◽  
Libo Cao ◽  
...  
Keyword(s):  
Regression Model ◽  
Body Posture ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body ◽  
Key Factor ◽  
Upper Body Posture ◽  
Spatial Coordinates ◽  
Posture Prediction ◽  
Connection Length

The driver’s whole-body posture at the time of a collision is a key factor in determining the magnitude of injury to the driver. However, current researchs on driver posture models only consider the upper body posture of the driver, and the lower body area which is not perceived by sensors is not studied. This paper investigates the driver’s posture and establishes a 3D posture model of the driver’s whole body through the application of machine vision algorithms and regression model statistics. This study proposes an improved Kinect-OpenPose algorithm for identifying the 3D spatial coordinates of nine keypoints of the driver’s upper body. The posture prediction regression model of four keypoints of the lower body is established by conducting volunteer posture acquisition experiments on the developed simulated driving seat and analyzing the volunteer posture data through using the principal components of the upper body keypoints and the seat parameters. The experiments proved that the error of the regression model in this paper is minor than that of current studies, and the accuracy of the keypoint location and the keypoint connection length of the established driver whole body posture model is high, which provides implications for future studies.

Influence of diet and exercise on skeletal muscle and visceral adipose tissue in men

1996 ◽  
Vol 81 (6) ◽  
pp. 2445-2455 ◽  
Author(s):  
Robert Ross ◽  
John Rissanen ◽  
Heather Pedwell ◽  
Jennifer Clifford ◽  
Peter Shragge
Keyword(s):  
Skeletal Muscle ◽  
Body Weight ◽  
Adipose Tissue ◽  
Visceral Adipose Tissue ◽  
Whole Body ◽  
Relative Reduction ◽  
Body Regions ◽  
Diet And Exercise ◽  
Magnetic Resonance Imaging Mri ◽  
Visceral Adipose

Ross, Robert, John Rissanen, Heather Pedwell, Jennifer Clifford, and Peter Shragge. Influence of diet and exercise on skeletal muscle and visceral adipose tissue in men. J. Appl. Physiol. 81(6): 2445–2455, 1996.—The effects of diet only (DO) and diet combined with either aerobic (DA) or resistance (DR) exercise on subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), lean tissue (LT), and skeletal muscle (SM) tissue were evaluated in 33 obese men (DO, n= 11; DA, n = 11; DR, n = 11). All tissues were measured by using a whole body multislice magnetic resonance imaging (MRI) model. Within each group, significant reductions were observed for body weight, SAT, and VAT ( P < 0.05). The reductions in body weight (∼10%) and SAT (∼25%) and VAT volume (∼35%) were not different between groups ( P > 0.05). For all treatments, the relative reduction in VAT was greater than in SAT ( P < 0.05). For the DA and DR groups only, the reduction in abdominal SAT (∼27%) was greater ( P < 0.05) than that observed for the gluteal-femoral region (∼20%). Conversely, the reduction in VAT was uniform throughout the abdomen regardless of treatment ( P > 0.05). MRI-LT and MRI-SM decreased both in the upper and lower body regions for the DO group alone ( P < 0.05). Peak O2 uptake (liters) was significantly improved (∼14%) in the DA group as was muscular strength (∼20%) in the DR group ( P< 0.01). These findings indicate that DA and DR result in a greater preservation of MRI-SM, mobilization of SAT from the abdominal region, by comparison with the gluteal-femoral region, and improved functional capacity when compared with DO in obese men.

Abstract 15080: Chronic Mild Sleep Curtailment Increases Markers of Adiposity While Maintained Healthy Sleep Reduces These Measures in Women

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Faris M Zuraikat ◽  
Samantha E Scaccia ◽  
Arindam RoyChoudhury ◽  
Marie-Pierre St-Onge
Keyword(s):  
Skeletal Muscle ◽  
Body Weight ◽  
Sleep Duration ◽  
Cardiovascular Health ◽  
Sleep Time ◽  
Whole Body ◽  
Body Volume ◽  
Insufficient Sleep ◽  
Wrist Actigraphy ◽  
Sleep Condition

Introduction: Over one-third of US adults do not achieve adequate sleep duration of 7 or more h per night. Short sleep is linked to higher odds of cardiometabolic diseases, including obesity. However, whether prolonged insufficient sleep causes increased body weight or adiposity remains unclear. Objective: To compare, in women, changes in body weight and composition in response to prolonged mild sleep restriction (SR) vs maintenance of healthy, habitual sleep (HS). Methods: Women (n=55; age: 35±13 y; BMI: 25.5±3.5 kg/m 2 ) with average adequate sleep duration (total sleep time [TST]=455±23 min) took part in a randomized crossover study with two 6-wk phases: HS and SR. In HS, usual bed and wake times (determined from 2 wk wrist actigraphy and sleep logs) were maintained. In SR, TST was reduced by 1.5 h/night. Sleep was measured continuously and verified weekly for compliance. Body weight and composition were measured at 0 and 6 wk using magnetic resonance imaging (MRI). Linear-mixed models tested interactions of sleep condition with week on outcome measures. Results: Average TST was reduced in SR and unchanged in HS (-87±19 vs -7±26 min, P<0.01). Significant study condition by week interactions were observed for whole-body volume (WBV), waist circumference (WC), and skeletal muscle. In HS, WBV and WC decreased while these measures increased in SR (WBV: -0.47±0.22 vs 0.27±0.05 L, P=0.02; WC: -1.04 ± 0.78 vs 1.16 ± 0.54 cm, P=0.04). Results were similar for skeletal muscle (-0.19 ± 0.07 vs 0.17 ± 0.01 L, P<0.01). A trend for a reduction in weight was observed in HS relative to SR (-0.39±0.31 vs 0.34±0.09 kg, P=0.09). Conclusions: This is the first evidence that prolonged insufficient sleep leads to increased body size in women. Conversely, maintaining adequate sleep may improve body composition. Our data suggest that healthy sleep duration should be a key component of strategies to improve cardiovascular health in women.

Effects of epinephrine on regional free fatty acid and energy metabolism in men and women

1996 ◽  
Vol 270 (2) ◽  
pp. E259-E264 ◽  
Author(s):  
M. D. Jensen ◽  
P. E. Cryer ◽  
C. M. Johnson ◽  
M. J. Murray
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Fat Distribution ◽  
Normal Weight ◽  
Upper Body ◽  
Lower Body ◽  
Men And Women

Upper-body and lower-body adipocytes respond differently to physiological catecholamines in vitro. It is not known whether this is true in vivo or whether gender differences exist in the regional adipose tissue responses to epinephrine. These studies were therefore conducted to examine free fatty acid (FFA) release ([3H]palmitate) from lower-body (leg), splanchnic, and upper-body adipose tissue in normal-weight adult men (n = 8) and women (n = 7). In response to intravenous epinephrine (10 ng.kg-1.min-1), palmitate release increased (P < 0.01) in both men (168 +/- 10 to 221 +/- 15 mumol/min) and women (177 +/- 12 to 234 +/- 18 mumol/min). Basal leg palmitate release was similar in women and men (16.8 +/- 2.9 and 12.4 +/- 1.3 mumol/min, P = not significant) but doubled (P < 0.01) in response to epinephrine in men and was virtually unchanged in women. Splanchnic palmitate release increased (P < 0.05) in men (n = 6) but not in women (n = 6), whereas nonsplanchnic upper-body palmitate release increased more in women than in men. Upper-body (splanchnic and nonsplanchnic) palmitate release increased (P < 0.05) in both men and women in response to epinephrine. In summary, lower-body adipose tissue FFA release increased in response to epinephrine in men but not women, whereas upper-body palmitate release increased in both groups. These findings are consistent with some in vitro findings and suggest that catecholamine action may play a role in determining gender-based differences in body fat distribution.

scholarly journals Pre-Exercise Rehydration Attenuates Central Fatigability during 2-Min Maximum Voluntary Contraction in Hyperthermia

Medicina ◽  
2019 ◽  
Vol 55 (3) ◽  
pp. 66
Author(s):  
Kazys Vadopalas ◽  
Aivaras Ratkevičius ◽  
Albertas Skurvydas ◽  
Saulė Sipavičienė ◽  
Marius Brazaitis
Keyword(s):  
Body Weight ◽  
Physiological Stress ◽  
Maximum Voluntary Contraction ◽  
Thermal Strain ◽  
Plasma Osmolality ◽  
Voluntary Contraction ◽  
Whole Body ◽  
Knee Extensors ◽  
Lower Body ◽  
Whole Body Hyperthermia

Background and objectives: Hyperthermia with dehydration alters several brain structure volumes, mainly by changing plasma osmolality, thus strongly affecting neural functions (cognitive and motor). Here, we aimed to examine whether the prevention of significant dehydration caused by passively induced whole-body hyperthermia attenuates peripheral and/or central fatigability during a sustained 2-min isometric maximal voluntary contraction (MVC). Materials and Methods: Ten healthy and physically active adult men (21 ± 1 years of age) performed an isometric MVC of the knee extensors for 2 min (2-min MVC) under control (CON) conditions, after passive lower-body heating that induced severe whole-body hyperthermia (HT, Tre > 39 °C) with dehydration (HT-D) and after HT with rehydration (HT-RH). Results: In the HT-D trial, the subjects lost 0.94 ± 0.15 kg (1.33% ± 0.13%) of their body weight; in the HT-RH trial, their body weight increased by 0.1 ± 0.42 kg (0.1% ± 0.58%). After lower-body heating, the HT-RH trial (vs. HT-D trial) was accompanied by a significantly lower physiological stress index (6.77 ± 0.98 vs. 7.40 ± 1.46, respectively), heart rate (47.8 ± 9.8 vs. 60.8 ± 13.2 b min−1, respectively), and systolic blood pressure (−12.52 ± 5.1 vs. +2.3 ± 6.4, respectively). During 2-min MVC, hyperthermia (HT-D; HT-RH) resulted in greater central fatigability compared with the CON trial. The voluntary activation of exercising muscles was less depressed in the HT-RH trial compared with the HT-D trial. Over the exercise period, electrically (involuntary) induced torque decreased less in the HT-D trial than in the CON and HT-RH trials. Conclusions: Our results suggest that pre-exercise rehydration might have the immediate positive effect of reducing physiological thermal strain, thus attenuating central fatigability even when exercise is performed during severe (Tre > 39 °C) HT, induced by passive warming of the lower body.

Gender differences in power production, energetic capacity and efficiency of elite cross-country skiers during whole-body, upper-body, and arm poling

2015 ◽  
Vol 116 (2) ◽  
pp. 291-300 ◽  
Author(s):  
Ann Magdalen Hegge ◽  
Elias Bucher ◽  
Gertjan Ettema ◽  
Oliver Faude ◽  
Hans-Christer Holmberg ◽  
...  
Keyword(s):  
Gender Differences ◽  
Power Production ◽  
Upper Body ◽  
Whole Body ◽  
Cross Country

Biology of upper-body and lower-body adipose tissue—link to whole-body phenotypes

2014 ◽  
Vol 11 (2) ◽  
pp. 90-100 ◽  
Author(s):  
Fredrik Karpe ◽  
Katherine E. Pinnick
Keyword(s):  
Adipose Tissue ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body

scholarly journals A combination of exercise and capsinoid supplementation additively suppresses diet-induced obesity by increasing energy expenditure in mice

2015 ◽  
Vol 308 (4) ◽  
pp. E315-E323 ◽  
Author(s):  
Kana Ohyama ◽  
Yoshihito Nogusa ◽  
Katsuya Suzuki ◽  
Kosaku Shinoda ◽  
Shingo Kajimura ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Body Weight ◽  
Adipose Tissue ◽  
Weight Gain ◽  
Energy Expenditure ◽  
Body Weight Gain ◽  
Whole Body ◽  
Voluntary Running ◽  
Running Wheel Exercise ◽  
Body Energy

Exercise effectively prevents the development of obesity and obesity-related diseases such as type 2 diabetes. Capsinoids (CSNs) are capsaicin analogs found in a nonpungent pepper that increase whole body energy expenditure. Although both exercise and CSNs have antiobesity functions, the effectiveness of exercise with CSN supplementation has not yet been investigated. Here, we examined whether the beneficial effects of exercise could be further enhanced by CSN supplementation in mice. Mice were randomly assigned to four groups: 1) high-fat diet (HFD, Control), 2) HFD containing 0.3% CSNs, 3) HFD with voluntary running wheel exercise (Exercise), and 4) HFD containing 0.3% CSNs with voluntary running wheel exercise (Exercise + CSN). After 8 wk of ingestion, blood and tissues were collected and analyzed. Although CSNs significantly suppressed body weight gain under the HFD, CSN supplementation with exercise additively decreased body weight gain and fat accumulation and increased whole body energy expenditure compared with exercise alone. Exercise together with CSN supplementation robustly improved metabolic profiles, including the plasma cholesterol level. Furthermore, this combination significantly prevented diet-induced liver steatosis and decreased the size of adipocyte cells in white adipose tissue. Exercise and CSNs significantly increased cAMP levels and PKA activity in brown adipose tissue (BAT), indicating an increase of lipolysis. Moreover, they significantly activated both the oxidative phosphorylation gene program and fatty acid oxidation in skeletal muscle. These results indicate that CSNs efficiently promote the antiobesity effect of exercise, in part by increasing energy expenditure via the activation of fat oxidation in skeletal muscle and lipolysis in BAT.

Whole-body skeletal muscle mass is not related to glucose tolerance or insulin sensitivity in overweight and obese men and women

2008 ◽  
Vol 33 (4) ◽  
pp. 769-774 ◽  
Author(s):  
Jennifer L. Kuk ◽  
Katherine Kilpatrick ◽  
Lance E. Davidson ◽  
Robert Hudson ◽  
Robert Ross
Keyword(s):  
Skeletal Muscle ◽  
Adipose Tissue ◽  
Insulin Sensitivity ◽  
Glucose Tolerance ◽  
Muscle Mass ◽  
Visceral Adipose Tissue ◽  
Skeletal Muscle Mass ◽  
Whole Body ◽  
Men And Women ◽  
Visceral Adipose

The relationship between skeletal muscle mass, visceral adipose tissue, insulin sensitivity, and glucose tolerance was examined in 214 overweight or obese, but otherwise healthy, men (n = 98) and women (n = 116) who participated in various exercise and (or) weight-loss intervention studies. Subjects had a 75 g oral glucose tolerance test and (or) insulin sensitivity measures by a 3 h hyperinsulinemic–euglycemic clamp technique. Whole-body skeletal muscle mass and visceral adipose tissue were measured using a multi-slice magnetic resonance imaging protocol. Total body skeletal muscle mass was not associated with any measure of glucose metabolism in men or women (p > 0.10). These observations remained independent of age and total adiposity. Conversely, visceral adipose tissue was a significant predictor of various measures of glucose metabolism in both men and women with or without control for age and (or) total body fat (p < 0.05). Although skeletal muscle is a primary site for glucose uptake and deposition, these findings suggest that unlike visceral adipose tissue, whole-body skeletal muscle mass per se is not associated with either glucose tolerance or insulin sensitivity in overweight and obese men and women.

scholarly journals Gender Differences in the Appetite Response to a Satiating Diet

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Alexandra Bédard ◽  
Anne-Marie Hudon ◽  
Vicky Drapeau ◽  
Louise Corneau ◽  
Sylvie Dodin ◽  
...  
Keyword(s):  
Gender Differences ◽  
Body Weight ◽  
Food Consumption ◽  
Premenopausal Women ◽  
Gender Issues ◽  
Men And Women ◽  
Time Interaction ◽  
Desire To Eat ◽  
Analogue Scales ◽  
Over Time

We examined gender differences in appetite sensations when exposed to Mediterranean diet (MedDiet) meals and determined whether there are gender differences in the change in the satiating properties of the MedDiet over time. Thirty-eight men and 32 premenopausal women consumed a 4-week isoenergetic MedDiet under controlled conditions. Visual analogue scales were used to measure perceived appetite sensations before and immediately after each meal consumed over the course of one day (Wednesday) of the first and the fourth week of intervention. Women reported greater decreases for desire to eat, hunger, and appetite score than men in response to the consumption of the MedDiet meals (gender-by-meal interactions, resp.,P=0.04,P=0.048, andP=0.03). Fullness and prospective food consumption responses did not significantly differ between men and women. Between the first and the fourth week of intervention, premeal prospective food consumption increased with time in men (P=0.0007) but not in women (P=0.84;Pfor gender-by-time interaction = 0.04). These results indicate gender differences in appetite sensations when exposed to the MedDiet. These results may be useful in order to have a better understanding of gender issues for body weight management.

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