PHSL 3051 Lab 5 2024 PDF

PHSL 3051 LAB 5: MECHANICS OF MUSCLE CONTRACTION DRAMATIC CHANGES IN BODY BUILDERS PHYSIQUES FROM THE 20TH CENTURY TO RECENT PAST Calum Eugen Arnold von Moger Sandow Schwarzenegger WORLDS FI...

PHSL 3051 LAB 5: MECHANICS OF MUSCLE CONTRACTION DRAMATIC CHANGES IN BODY BUILDERS PHYSIQUES FROM THE 20TH CENTURY TO RECENT PAST Calum Eugen Arnold von Moger Sandow Schwarzenegger WORLDS FITTEST GRANDMA 87 YEAR OLD ERNESTINE SHEPHERD  93 YEAR OLD IRISH ROWING CHAMPION RICHARD MORGAN For lessons on how to age well, we could do worse than turn to Richard Morgan. At 93, the Irishman is a four-time world champion in indoor rowing, with the aerobic engine of a healthy 30- or 40-year- old and the body-fat percentage of a whippet. He’s also the subject of a new case study, published last month in the Journal of Applied Physiology, that looked at his training, diet and physiology. Its results suggest that, in many ways, he’s an exemplar of fit, healthy aging — a nonagenarian with the heart, muscles and lungs of someone less than half his age. But in other ways, he’s ordinary: a onetime baker and battery maker with creaky knees who didn’t take up regular exercise until he was in his 70s and who still trains mostly in his backyard shed. SCIENTIFIC DOCUMENTATION OF MR. MORGAN’S FITNESS Allison Gerads (gophersports.com Dec, 2021) Gable Steveson (gophersports.com, 2022) Ali Weimer (gophersports.com,11/22) 12th Midwest NCAA 20:28.50 min Amira Young (gophersports.com, 2023) 7.19s in the 60m (new B10 record) A SELECTION OF GOPHER ATHLETES  Pharrel Payne (gophersports.com Feb, 2024) Sophie Hart (gophersports.com, 2022) Emmet Anderson (gophersports.com,5/23) Amira Young (gophersports.com, 2023) BIG Outdoor Track and Field Championships 7.19s in the 60m (new B10 record) A SELECTION OF GOPHER ATHLETES OTHER ATHLETES FROM OUR REGION SUNI LEE OTHER ATHLETES FROM OUR REGION ANTHONY EDWARDS Simone Biles Dirk Nowitzki 4 ft. 8 in. 7 ft. Elite athletes come in all sizes SKELETAL MUSCLE: MECHANICS OF SINGLE FIBER CONTRACTION Isometric Isotonic Latent Period 30 Isometric Latent Period Tension (mg) 20 Isotonic 10 10 Figure 9-16 11  SKELETAL MUSCLE: MECHANICS OF SINGLE FIBER CONTRACTION Isometric Contraction 35 Force required to move load 30 Muscle Tension developed (kg) relaxes Muscle 25 contracts 20 15 Muscle 10 relaxes 5 Load does 30 kg 30 kg not move. Time Muscle stimulated Figure 12-18b Isometric Contraction 12  SKELETAL MUSCLE: MECHANICS OF SINGLE FIBER CONTRACTION Isotonic Contraction 35 30 Muscle Tension developed (kg) relaxes Muscle contracts 25 Force required to move load 20 15 Muscle 10 relaxes 20 kg 5 20 kg Load Time moves. Muscle stimulated Figure 12-18a Isotonic contraction 13 ` THE PLAN FOR TODAY’S LAB SESSION This lab allows the measurement of human muscle contraction initiated by electrical stimulation and thus mimics the process of EXCITATION-CONTRACTION COUPLING that normally occurs in the body. Human muscle nerves can be directly stimulated through the skin at particularly sensitive spots known as MOTOR POINTS. These motor points are directly over areas where the nerves enter the muscle. MOTOR POINTS Human muscle nerves can be stimulated through the skin at positions known as MOTOR POINTS. These motor points are close enough to the surface to be directly stimulated. We will be attempting to stimulate the median nerve to stimulate flexor digitorum superficialis. The median nerve originates from the brachial plexus with roots from C6, C7, C8, & T1. MOVEMENTS OF THE MUSCLE FLEXOR DIGITORUM SUPERFICIALIS Stimulation of the motor point of flexor digitorum superficialis causes the fingers to flex as if in a grasping motion. FINDING THE MOTOR POINT https://www.youtube.com/watch?v=hdFZLUx36rY BIOPAC DISPLACEMENT SENSOR Measures displacement (movement) of a finger. The device has been calibrated to report centimeters moved in response to an electrical stimulus. We are not measuring muscle tension (or force) with this device. HUMAN SAFE STIMULATOR IN THE LAB Class will divide into two sections for the exercise There are 14 stations set up No more than 6 students per station Designate computer operators for each trial Designate at least two volunteer subjects for the lab exercises You will have ~40 minutes to collect and review data LAB 5 BIOPAC COMPUTER During the exercise, the computer screen will show two graphs The upper graph will be displacement vs. time and tracks finger movement. The lower graph will be voltage vs. time and will track stimulation intensity (amplitude) and frequency. displacement vs. time Stimulation vs. time HAPPY VALENTINES DAY!