scholarly journals WORK MOTION STUDY OF PIVOT TYPE TRAILER OPERATION ON TWO WHEEL TRACTORS

2021 ◽  
pp. 82-91
Author(s):  
Muhammad Dhafir ◽  
Muhammad Idkham ◽  
Safrizal Safrizal ◽  
Agus Arip Munawar
Keyword(s):  
Data Collection ◽  
Range Of Motion ◽  
Upper Body ◽  
Lower Body ◽  
Body Segments ◽  
Video Recordings ◽  
Motion Study ◽  
Ergonomic Interventions

This study aims to analyze the pivot type trailer operation with an ergonomic approach and the necessary interventions required to minimize work risks. Data collection was carried out using questionnaires and video recordings of the operators when the tractors as well as trailers were being operated at various conditions such as track, load, speed, straight motion or turn. Based on the Range of Motion (ROM) analysis, it was discovered that while operating this pivot type trailer, the upper body segments, such as neck, shoulders, elbows and back of the operator, comfortably controlled the tractor. Meanwhile, in the lower body segments, such as the thighs and knees, the operator generally felt discomfort. Furthermore, the analysis of the operator's subjectivity perception showed that discomfort was felt at several segments of the upper and lower body, such as the hands and knees. Therefore, several ergonomic interventions are required to increase the comfort of operating this pivot type trailer.

Effect of a Supervised Stretching Program on Neck, Shoulder, and Trunk Range of Motion in Older Women

2021 ◽  
pp. 1-7
Author(s):  
Sandra C. Webber ◽  
Michelle M. Porter
Keyword(s):  
Range Of Motion ◽  
Older Women ◽  
Intervention Group ◽  
Field Tests ◽  
Community Dwelling ◽  
Upper Body ◽  
Lower Body ◽  
Power Training ◽  
And Control ◽  
Lower Body Power

Abstract Upper body and neck range of motion (ROM) are important for safe walking and driving. The purpose of this study was to determine whether stretching would improve neck, trunk, and shoulder ROM. Forty-eight community-dwelling women (75 ± 3 years of age) were randomly allocated to intervention (upper body stretching, n = 15) and control conditions (lower body power training, n = 33). All participants exercised in supervised 45-minute sessions twice weekly for 12 weeks. Testing of upper body ROM included a cervical ROM, device-based measurement and field tests of the neck, trunk, and shoulder ranges. Shoulder ROM was the only movement that improved in the intervention group beyond levels seen in control participants (33% increase, p < 0.01). Neck and trunk ROM did not change in response to a specific stretching program. Older adults with ROM limitations may need to explore other exercise options or focus on compensatory strategies for safe community mobility.

scholarly journals Central aortic hemodynamics following acute lower and upper-body exercise in a cold environment among patients with coronary artery disease

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Heidi E. Hintsala ◽  
Rasmus I. P. Valtonen ◽  
Antti Kiviniemi ◽  
Craig Crandall ◽  
Juha Perkiömäki ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Dynamic Exercise ◽  
Upper Body ◽  
Cold Environment ◽  
Lower Body ◽  
Static Exercise ◽  
Upper Body Exercise ◽  
Post Exercise ◽  
Artery Disease

AbstractExercise is beneficial to cardiovascular health, evidenced by reduced post-exercise central aortic blood pressure (BP) and wave reflection. We assessed if post-exercise central hemodynamics are modified due to an altered thermal state related to exercise in the cold in patients with coronary artery disease (CAD). CAD patients (n = 11) performed moderate-intensity lower-body exercise (walking at 65–70% of HRmax) and rested in neutral (+ 22 °C) and cold (− 15 °C) conditions. In another protocol, CAD patients (n = 15) performed static (five 1.5 min work cycles, 10–30% of maximal voluntary contraction) and dynamic (three 5 min workloads, 56–80% of HRmax) upper-body exercise at the same temperatures. Both datasets consisted of four 30-min exposures administered in random order. Central aortic BP and augmentation index (AI) were noninvasively assessed via pulse wave analyses prior to and 25 min after these interventions. Lower-body dynamic exercise decreased post-exercise central systolic BP (6–10 mmHg, p < 0.001) and AI (1–6%, p < 0.001) both after cold and neutral and conditions. Dynamic upper-body exercise lowered central systolic BP (2–4 mmHg, p < 0.001) after exposure to both temperatures. In contrast, static upper-body exercise increased central systolic BP after exposure to cold (7 ± 6 mmHg, p < 0.001). Acute dynamic lower and upper-body exercise mainly lowers post-exercise central BP in CAD patients irrespective of the environmental temperature. In contrast, central systolic BP was elevated after static exercise in cold. CAD patients likely benefit from year-round dynamic exercise, but hemodynamic responses following static exercise in a cold environment should be examined further.Clinical trials.gov: NCT02855905 04/08/2016.

Upper Body Aerobic Exercise as a Possible Predictor of Lower Body Performance

2015 ◽  
Vol 86 (7) ◽  
pp. 599-605 ◽  
Author(s):  
Carl J. Ade ◽  
Ryan M. Broxterman ◽  
Jesse C. Craig ◽  
Susanna J. Schlup ◽  
Samuel L. Wilcox ◽  
...  
Keyword(s):  
Aerobic Exercise ◽  
Upper Body ◽  
Lower Body

scholarly journals Effects of the lower jaw position on athletic performance of elite athletes

2020 ◽  
Vol 6 (1) ◽  
pp. e000886
Author(s):  
John Patrick Haughey ◽  
Peter Fine
Keyword(s):  
Athletic Performance ◽  
Positive Impact ◽  
Elite Athletes ◽  
Upper Body ◽  
Lower Body ◽  
Lower Jaw ◽  
Hamstring Flexibility ◽  
Jaw Position ◽  
Upper Body Power ◽  
Lower Body Power

When an athlete wears a mouthguard, the position of the lower jaw is changed by virtue of the teeth being unable to occlude. Little research is available in in this area, which have indicated both positive impact and no positive impact.ObjectivesThis study aims to explore the influence of the lower jaw position on athletic performance in elite athletes.MethodsA repeated measures study compared two lower jaw positions, the athlete’s normal (habitual) bite and the lower jaw position when the muscles of mastication are at physiological rest (physiological rest bite). 15 athletes completed a medicine ball putt (upper body power), vertical jump (lower body power), sit and reach (composite hamstring flexibility), passive knee flexion (hamstring muscle length) and star excursion balance (stability and balance) tests in each condition.ResultsPaired t-tests showed the physiological rest bite had significant (p<0.05) positive effect on athletic performance for each test. On average the physiological rest bite provided an increase of lower body power (5.8%), upper body power (10%), hamstring flexibility (14%) and balance and stability (4.8%) compared to the habitual bite.ConclusionThis study provides evidence of the need for further research to confirm if the lower jaw position can be optimised for athletic performance in athletes.

Analysis of Power Output Time Series in Response to Supramaximal Exercise: An Approach Through Dynamic Factor Analysis

2011 ◽  
Vol 23 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Paula Marta Bruno ◽  
Fernando Duarte Pereira ◽  
Renato Fernandes ◽  
Gonçalo Vilhena de Mendonça
Keyword(s):  
Factor Analysis ◽  
Power Output ◽  
Soccer Players ◽  
Upper Body ◽  
Dynamic Factor Analysis ◽  
Dynamic Factor ◽  
Lower Body ◽  
Supramaximal Exercise ◽  
Output Time ◽  
Pattern Of Variation

The responses to supramaximal exercise testing have been traditionally analyzed by means of standard parametric and nonparametric statistics. Unfortunately, these statistical approaches do not allow insight into the pattern of variation of a given parameter over time. The purpose of this study was to determine if the application of dynamic factor analysis (DFA) allowed discriminating different patterns of power output (PO), during supramaximal exercise, in two groups of children engaged in competitive sports: swimmers and soccer players. Data derived from Wingate testing were used in this study. Analyses were performed on epochs (30 s) of upper and lower body PO obtained from twenty two healthy boys (11 swimmers and 11 soccer players) age 11–12 years old. DFA revealed two distinct patterns of PO during Wingate. Swimmers tended to attain their peak PO (upper and lower body) earlier than soccer players. As importantly, DFA showed that children with a given pattern of upper body PO tend to perform similarly during lower body exercise.

Cardiorespiratory responses to exercise distributed between the upper and lower body

1983 ◽  
Vol 54 (5) ◽  
pp. 1403-1407 ◽  
Author(s):  
M. M. Toner ◽  
M. N. Sawka ◽  
L. Levine ◽  
K. B. Pandolf
Keyword(s):  
Respiratory Exchange Ratio ◽  
Venous Return ◽  
Minute Ventilation ◽  
Peripheral Resistance ◽  
Upper Body ◽  
Lower Body ◽  
Upper Body Exercise ◽  
Cardiorespiratory Responses ◽  
Muscle Groups ◽  
Constant Power Output

The present study examined the influence that distributing exercise between upper (arm crank exercise) and lower (cycle exercise) body muscle groups had on cardiorespiratory responses to constant power output (PO) exercise. Six male volunteers completed five submaximal exercise bouts of 7-min duration at both 76 and 109 W. The arm PO/total PO (% arm) for these bouts was approximately 0, 20, 40, 60, and 100%. At 76 W, O2 uptake (VO2) did not change (P greater than 0.05) from 0 to approximately 20% arm (approximately 1.30 1 x min-1) but increased with increasing percent arm values up to 100% (1.58 1 x min-1). At 109 W, VO2 increased throughout the range of 0 (1.70 1 x min-1) to 100% arm (2.33 1 x min-1). In general, minute ventilation (VE) and respiratory exchange ratio (R) increased with increased percent arm values at 76 and 109 W. The heart rate (HR) responses remained unchanged from 0 to 60% arm at both 76 and 109 W; however, between 60 and 100% arm, a 26-beats x min-1 increase was observed at 76 W (143 beats x min-1 at 100% arm) and a 45-beats x min-1 increase at 109 W (174 beats x min-1 at 100% arm). These data suggested that during upper body exercise, the increased VO2 associated with increased percent arm values was not accompanied by an elevated HR response when at least 40% of the PO was performed by the lower body. This might be attributed to a facilitated venous return and/or a decreased total peripheral resistance when the lower body was involved in the exercise.

Isotope tracer measures of meal fatty acid metabolism: reproducibility and effects of the menstrual cycle

2005 ◽  
Vol 288 (3) ◽  
pp. E547-E555 ◽  
Author(s):  
Ana Paola Uranga ◽  
James Levine ◽  
Michael Jensen
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Menstrual Cycle ◽  
Dietary Fat ◽  
Fatty Acid Uptake ◽  
Upper Body ◽  
Acid Oxidation ◽  
Acid Uptake ◽  
Lower Body

Oxidation and adipose tissue uptake of dietary fat can be measured by adding fatty acid tracers to meals. These studies were conducted to measure between-study variability of these types of experiments and assess whether dietary fatty acids are handled differently in the follicular vs. luteal phase of the menstrual cycle. Healthy normal-weight men ( n = 12) and women ( n = 12) participated in these studies, which were block randomized to control for study order, isotope ([3H]triolein vs. [14C]triolein), and menstrual cycle. Energy expenditure (indirect calorimetry), meal fatty acid oxidation, and meal fatty acid uptake into upper body and lower body subcutaneous fat (biopsies) 24 h after the experimental meal were measured. A greater portion of meal fatty acids was stored in upper body subcutaneous adipose tissue (24 ± 2 vs. 16 ± 2%, P < 0.005) and lower body fat (12 ± 1 vs. 7 ± 1%, P < 0.005) in women than in men. Meal fatty acid oxidation (3H2O generation) was greater in men than in women (52 ± 3 vs. 45 ± 2%, P = 0.04). Leg adipose tissue uptake of meal fatty acids was 15 ± 2% in the follicular phase of the menstrual cycle and 10 ± 1% in the luteal phase ( P = NS). Variance in meal fatty acid uptake was somewhat ( P = NS) greater in women than in men, although menstrual cycle factors did not contribute significantly. We conclude that leg uptake of dietary fat is slightly more variable in women than in men, but that there are no major effects of menstrual cycle on meal fatty acid disposal.

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.

scholarly journals The relationship between second-to-fourth digit ratio (2D:4D), muscle strength and body composition to bone mineral density in young women

Kinesiology ◽  
2019 ◽  
Vol 51 (2) ◽  
pp. 238-245
Author(s):  
Hamid Arazi ◽  
Ehsan Eghbali
Keyword(s):  
Body Composition ◽  
Muscle Strength ◽  
Young Women ◽  
Upper Body ◽  
Lower Body ◽  
Fat Percentage ◽  
Mineral Density ◽  
Body Strength ◽  
Lower Body Strength ◽  
The Relationship

2D:4D ratio is determined by balance between androgens and estrogens. Low level estrogen reduces bone mineral density (BMD) and incurs negative changes to bone microarchitecture, increasing the risk of osteoporosis and, as a consequence, fracture risk in women. The purpose of this study was to investigate the relationship between 2D:4D, muscle strength and body composition to BMD in young women. One hundred twenty-seven young women (age range 24-36 years) voluntarily participated in this study. Lengths of the second (index) and fourth (ring) fingers, upper and lower body strength and body composition (body mass index, BMI; waist to hip ratio, WHR) and body fat percentage were estimated. Also, blood levels of calcium and 25-hydroxyvitamin D (25OHD) were evaluated and dual-energy X-ray absorptiometry device was used to measure BMD in the lumbar spine (LS) and femoral neck (FN). The results showed that digit ratios, upper body and lower body muscle strength, BMI and fat percentage had a positive relationship with LS and FN BMD (LS BMD: r=.47, r=.56, r=.46, r=.34, r=.28, p≤.001, respectively; FN BMD: r=.34, r=.49, r=.51, r=.45, r=.27, p≤.001, respectively). In addition, there was no significant relationship between WHR and BMD of LS and FN (p˃.05). Multiple linear regression analysis showed the upper body strength was a stronger determinant of LS BMD and the lower body strength was a stronger determinant of FN BMD. Based on the results, the researchers concluded that upper and lower body strength, 2D:4D ratios and BMI were important determinants of young women’s BMD. Also, it seemed that some of these factors may be able to help predicting the osteoporosis potential in young women

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