Fitness applications - objectives To develop a knowledge and understanding of: The role of biomechanics in fitness programing Fitness objectives and conditioning principles Biomechanics principles in the design and conduct of resistive, aerobic, and flexibility exercise Design, evaluation, and selection of resistive and aerobic exercise equipment Exercises and exercise equipment of questionable value

Fitness Applications: Introduction References (on reserve): –Kreighbaum & Barthels (1996). Biomechanics: A qualitatibve approach for studying human movement. Chapter 8 – pp –Baechle (2000). Essentials of Strength Training and Conditioning. Ch 3 Role of Biomechanics in Fitness Programming –Anatomical-mechanical analyses of exercise design (What exercises to do?) – Anatomical-mechanical analyses of exercises (Technique, or how to do it?) – Mechanical analysis of exercise equipment (Design and selection) Objectives of most fitness programs are to improve: –Muscular Strength –Skeletal strength –Muscular Endurance –Flexibility –Cardiorespiratory Endurance

General fitness conditioning principles Important conditioning principles: – Progressive overload – Specificity of training – SAID principle movement pattern, joint position, speed, type of contraction Remember which aspect of fitness you are working on and apply the overload and specificity principles appropriately What is the stimulus for improvement of each fitness element?

Biomechanics of Resistive exercises Factors affecting force application –Force-velocity relationship –Strength-joint position relationship (combination of angle of pull and force/length relationship) Should we provide the same degree of overload throughout the movement? If so, how do we do it?

Use of Cams in Ex Equipment: Why?

Recommended forearm flexion exercise – Variable resistance, NATURALLY! Effect of speed on torque during exercise: Torque = Wd + MOI x ang acc

Recommended Extension Exercise – variable resistance, NATURALLY! Effect of speed on torque during exercise: Torque = Wd + MOI x ang acc

Developing Muscular Strength Muscular Strength - ability of segment to exert force (MVC) –Overload stimulus is tension (use resistance equal to or greater than 10 RM ) –Factors affecting force application: Force-velocity relationship Strength-joint position relationship (combination of angle of pull and force/length relationship) –Focus on fundamental movements, antigravity musculature, and proportionate development –Specificity principle applies to: body position speed and type of contraction –Concentric –Eccentric –Isometric range of motion movement pattern pre-contraction stretch condition (plyometrics)

Developing Muscular Endurance Mucular Endurance- ability to repeat or sustain submaximal contractions –Overload stimulus is work intensity –Use load approx 60% of max strength, or < 10 RM –Focus on fundamental movements, antigravity musculature, and proportionate development –Specificity principle applies to resistance, body position, speed, cadence, ROM, and total number of reps Cardiorespiratory Endurance - Aerobic capacity –Overload stimulus is VO 2 max, Cardiac output, or Heart Rate –Repetition and resistance relative to muscular strength/endurance are important –Remember specificity principle regarding gravity, muscles involved

Developing Skeletal Strength Overload stimulus is strain (normalized deformation ) Remember 4 loading modes –Compression –Tension –Torsion –Shear Exercise in gravitational environment and emphasize weight bearing and resistive exercises Skeletal strength is developed concomitantly with muscular strength development The best way to prevent osteoporosis is to build up bone mineral content (BMC) during childhood, adolescence and early adulthood

Sample Resistive Exercise Program Basic Program - required –Squat with heel raise – Trunk curl (goal is 30 reps) – Bench press – Sit or bent row – Upright press – Pull downs or chins Optional exercises –Back extension from prone position – Forearm curl –Forearm extension or dips Note: This program incorporates the principles of bilateral and agonistic- antagonistic balance and focuses on muscular strength and endurance development of the antigravity musculature. At least two sets (one with light weight for warm- up), and preferably three sets, of each exercise should be completed at RM. What exercises would you change or add?

Understanding questions related to biomechanics of fitness Devise a series of exercises for strengthening the triceps brachii. Recall its functions at both joints, its three proximal attachments, its possibility for length-tension adjustments, and its potential for active and passive insufficiency. What is the overload stimulus for development of each of the following fitness elements? (1) Muscular strength, (2) muscular endurance, (3) flexibility, (4) bone strength, (5) cardiorespiratory endurance. Explain two ways that resistance changes during the movement of a gravity-dependent exercise using free weights or the body as the resistance. What is a variable resistance exercise machine? What is the reason for their design and use?

Understanding questions Explain why it is so important to do gravity-dependent resistive exercises slowly. Compare the difficulty of doing straight-leg situps with (a) the hands beside the neck, (b) the arms crossed over the shoulders, and © the arms at the sides. Explain the differences in difficulty in terms of motive and resistive torques and muscle groups being used. Name a flexibility test that you have taken in the past that is biased for or against people with different body segment proportions. Why is the timed situp test with the feet anchored ill advised?

Criteria for Resistive Equipment Selection Can you apply specificity principles appropriately? –Type of contraction, movement pattern, speed –Carryover to living in gravitational environment? Is resistance enough to accomodate your strength ? Does it fit different sized people? Is it safe? Is it uncomplicated to use (user friendly) Is there scientific evidence to support manufacturer’s claims? Does the equipment follow a normal neuromuscular pattern? If variable resistance, does resistance follow normal strength-position curve? Does it have motivation-enhancing features?

Relevant Questions for, or Criteria, for Aerobic Exercise Type and Equipment Selection Exercise modes include walking, running, stair climbing, bicycling, rowing, skiing, swimming Equipment simulates some activities using large proportion of total body musculature Evaluate each mode relative to the following criteria –Degree of overload on cardiorespiratory system –Relevance to fundamental movements and ADL’s –Proportion of total body musculature involved –Degree of compressive stress on femoral head and lumbar vertebral bodies (sites of most osteoporotic fractures) –Compressive stress on patella and knee joint –Range of motion and torque at hip, knee, and lumbar spine –Motivational features (comfort, user friendly, feedback, RPE) –Likelihood of continued usage –Cost –Other?

Comparison of Aerobic Ex Modes

Questionable exercises Hyperextended back Good morning exercise Straight leg deadlift Deep knee bends beyond thighs parallel Ballistic rotation movements of spine Behind neck press Bouncing and jumping with one-legged landings

Questionable exercises:

It depends on how you do it!

Abdominal Exercises: When knees are straight, hip flexors initiate the situp movement by forward rotation of the pelvic, exaggerating the posterior lumbar curve. Anchoring the feet enables hip flexors to contribute to the situp, lowering abdominal muscle activity. What is the effect of the inclined board?