Viscoelastic and Viscoplastic Glucose Theory (VGT #34): Applying VEGT and Viscoelastic Perturbation Model and Using Carbs/Sugar Intake Amount Along with Post-Meal Walking K-Steps as Two Constant Viscosity Factors to Predict Two LEGT PPG Values from 8/8/2018 to 2/26/2022 Based on GH-Method: MathPhysical Medicine (No. 615)

Abstract

The author has studied strength of materials and theory of elasticity through his undergraduate courses at the University of Iowa (UI). He also conducted research work and earned a master’s degree in Biomechanics under Professor James Andrews. In 1970-1971, he used a combined spring and dashpot model to simulate the behaviors of human joints, bones, muscles, and tendons, where he took some related courses at the UI School of Medicine, to investigate the soldier-weapon biophysical interactions during the Vietnam war era. Next, he went to MIT to pursue his PhD study under Professor Norman Jones, who taught him theory of plasticity and dynamic plastic behaviors of various structure elements. To further his education, he took additional graduate courses in various fields of fluid dynamics, thermodynamics, bridge design using energy absorption pad, and soil mechanics under earthquake forces which deal with “time-dependent issues”. Since then, many advancements have been made in the biomechanics branch, especially with human body live tissues that possess certain viscoelastic characteristics, such as bones, muscles, cartilages, tendons (connect bone to muscle), ligaments (connect bone to bone), fascia, and skin. For example, the author suffered plantar fasciitis for many years. He understood that calf stretching exercises or wearing the night splint dorsiflexes forefoot, at the back of the foot, increases plantar fascia tension to offer stress-relief from the pain. This model where muscles and tendons connect the lower leg and foot is a form of viscoelastic study for medical problem solving. When dealing with human internal organs, it is not easy to conduct live experiments to obtain accurate measurements for the biomedical material properties. Blood itself is a viscous material (time-dependent) and its viscosity factor may fall between water, honey, syrup, or gel. However, the author’s research focus is on “glucose” where the blood sugar amount is produced by the liver and carried by red blood cells, not the blood itself. It is nearly impossible to measure the material geometry or material properties to determine the viscosity of glucose, like in engineering research work. Although postprandial plasma glucose (PPG) is strongly influenced by both energy input via carbs/sugar intake amount (~60%) and energy output via post-meal exercise level (~40%). Fundamentally, the PPG level is also dependent upon the individual's health conditions in regard to liver cells and pancreatic beta cells, which produce glucose and release insulin to control the glucose level in blood. Therefore, the author selects a combined value of (carbs/sugar grams and post-meal walking k-steps with respective weighting factors of GH-Modulus as the viscosity factor (η). Based on this knowledge, he applies the “concept” of viscoelasticity and viscoplasticity” to construct an analogy model of time-dependent glucose behaviors.