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Standing as a Solution
Published in Robert Bridger, A Guide to Active Working in the Modern Office, 2019
The BMI of individuals is calculated by dividing their body mass in kilograms by their height squared in meters. For example, a man weighing 80kg standing 1.8m tall would have a BMI of 24.7 (80/(1.8x.18)). The model includes waist circumference to account for the fact that very muscular individuals may have a high BMI but be perfectly healthy. The health risk is associated with high levels of fat, particularly in the abdomen, rather than overall body mass.
An image-based shape analysis approach and its application to young women’s waist-hip-leg position
Published in Ergonomics, 2023
Yupeng Hu, Yuanping Xia, Bingfei Gu
According to ISO 8559-1-2017, the waist level is defined as the midway between the lowest rib point and the highest point of the hip bone at the side of the body. However, since this landmark is very difficult to be identified, we found that the error is very large after measuring even the same person twice by different people. In order to ensure the accuracy, we took the navel position as the reference position. The abdomen refers to the region between the pelvis and the thorax. The hip level is defined as the level of the greatest projection at the back of the body (buttocks). The inside leg level is defined as the level of the highest visible point at the junction between the right and left thighs observed from the back of the subject, and it can be considered as the crotch position. We use the maximum horizontal cross-section between the inside leg level and the knee level to represent the thigh position. The knee level is defined as the joint between the lower and upper leg. The calf level is the maximum level of the lower leg, taken between the knee and the ankle. The minimum leg level (ankle) is defined as the joint between the foot and the lower leg. Based on the definitions of the landmarks, the points of the navel area are taken as examples to explain the principle of each point in Table 1. From the front image, NP is the centre point of the navel line, and N1 and N2 are lateral projections of NP in the transversal plane. From the side image, N3 and N4 are posterior and anterior projections in the sagittal plane, respectively.
The effects of trunk endurance training on running kinematics and its variability in novice female runners
Published in Sports Biomechanics, 2021
Shinya Ogaya, Minami Suzuki, Chiori Yoshioka, Yumi Nakamura, Shunsuke Kita, Kento Watanabe
Trunk muscles such as transverse abdominis surround internal organs to form an outer wall of abdomen, and therefore the muscle activity contributes to stabilise trunk motion by increasing internal pressure in the abdomen and make an anatomical base of lower extremities during motion (Rivera, 2016; Sato & Mokha, 2009). A variety of studies have emphasised the importance of trunk muscle strength and endurance in controlling the trunk’s motion in order to enable the optimum production, transfer, and control of force and motion to the body’s distal segments (Kibler et al., 2006; Prieske et al., 2016; Willardson, 2007). Unstable trunk motion caused by muscle weakness results in additional and inefficient movement (Hart et al., 2009; Koblbauer et al., 2014), which decreases running economy (Fredericson & Moore, 2005). Weaken trunk muscles fail to maintain trunk posture and results in increased moment on the lower limbs during running (Koblbauer et al., 2014). Koblbauer investigated the potential effects of trunk muscle fatigue during high-intensity running and found that it can strongly impair running performance. Therefore, trunk muscle strength is essential for runners to improve their performance.