Muscular Strength and Endurance Chapter 4 Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 4 © McGraw-Hill Higher Education

Physical Activity Pyramid See Figure 2.4 Physical Activity Pyramid, page 30

Lecture Objectives Differentiate between fast twitch and slow twitch muscle fibers. Define muscular strength and muscular endurance. Explain the three types of muscle contractions. Explain benefits of muscular training and causes of differences in strength. Develop your own opinion on supplements and drugs supported by evidence from the book. State F.I.T.T. principles for muscular strength, muscular endurance, and general muscle fitness (health) and compare to F.I.T.T. principles for other components of fitness. Explain resistance training myths and why they are not true.

© McGraw-Hill Higher Education Muscle Physiology Muscle fibers Muscles consist of many muscle fibers (cells) connected in bundles Hypertrophy Strength training increases the number of myofibrils and the size of muscle fibers Atrophy Inactivity reverses the process Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 4 © McGraw-Hill Higher Education

Muscle Fibers  Slow-twitch fibers  Fast-twitch fibers --Fatigue resistant --Don’t contract as rapidly and forcefully as fast-twitch fibers --Rely primarily on oxidative energy system Fast-twitch fibers --Contract rapidly and forcefully --Fatigue more quickly than slow-twitch fibers --Rely more on nonoxidative energy system  Slow-twitch fibers  Fast-twitch fibers Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 4 © McGraw-Hill Higher Education

Definitions Muscular Strength Muscular Endurance Muscular Strength --The amount of force a muscle can produce with a single maximal effort. Muscular Endurance --The ability of a muscle or group of muscles to remain contracted or to contract repeatedly.

Neuromuscular adaptation!!!! Training Facts Synonyms Everyone can gain strength and endurance NOT everyone will improve to the same extent Physiological effects Synonyms Resistance training Strength training Weight training Different rates of improvement --Genetic predisposition --Adaptations depend largely on the muscle fiber type distribution. Fast twitch muscle fibers adapt more readily. Neuromuscular adaptation --Nerves adapting to resistance training and working more efficiently to activate muscles. Physiological effects --Muscle mass and size of muscle fibers --Utilization and coordination of motor units --Strength of tendons, ligaments, and bones --Storage of fuel in and blood supply to muscles --Improvements in blood fat levels and biochemical processes Neuromuscular adaptation!!!!

Isotonic Exercise Concentric vs. Eccentric Contractions (lengthening) LOWERING Concentric (shortening) LIFTING Concentric and eccentric phases are dynamic and can build muscle. Isometric -Static (isometric) exercise = muscle contraction without a change in the length of the muscle -Sticking point: point in ROM where weight can’t be lifted any farther without extreme effort or help -Advantages: low cost, can do anywhere, rehab an immobilized joint. -Disadvantages: builds strength at only one position, less muscle hypertrophy, poor transfer to sport skills Others Plyometrics = sudden eccentric loading and stretching followed by a concentric contraction Speed loading = moving a load as rapidly as possible Isometric - No movement takes place - Used at “sticking points” 20

Benefits of Muscular Fitness Improved performance of physical activities Injury prevention Improved body composition Enhanced self-image and quality of life Improved muscle and bone health with aging Prevention and management of chronic disease Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 4 © McGraw-Hill Higher Education

Differences in Strength Gender Age Anatomy Genetics Drugs Women have 60-85% of the absolute strength of men  less testosterone  less muscle mass Max strength reached by 20's, then decline. Longer limbs = advantage Can make muscles more efficient and effective through training. Steroids: weaken connective tissue --> injury HGH: increase in bone size --> many health risks, can decrease life by as much as twenty years. At what age does strength peak?

Differences in Strength = Weight lifted Body weight Relative Absolute = Weight lifted

Supplements and Drugs Increase intensity and overcome fatigue Amphetamines Caffeine Increase endurance Erythropoietin Darbepoetien Aid weight control Diethylpropion, phentermine Caffeine, PPA, ephedra Dinitrophenol Diuretics Increase muscle growth Anabolic steroids Growth hormone (HGH) Androstenedione IGF-1 Protein & amino acid supplements Speed recovery from training Creatine monohydrate Chromium picolinate Carbohydrate beverages Use as an example of potential side effects of supplements. Discuss need to know what you are taking, not just what it is supposed to do to your body. Refer to page 101 in book. Side effects of Anabolic steroids --Liver damage and tumors --Reduced HDL --High blood pressure, heart disease, cancer --Depressed immune function --Psychological disturbances --Depressed sperm and testosterone production; breast development in males --Masculinization in women and children --Premature closure of bone growth centers (See Table 4.2: Performance Aids Marketed to Weight Trainers, page 101)

Applying the FITT Principle Frequency = days per week Intensity = amount of resistance Time = number of repetitions and sets Type = strength training exercises for all major muscle groups Point out difference in Intensity and Time compared to other FITT principles. Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 4 © McGraw-Hill Higher Education

Muscular Fitness Training

F.I.T.T. F 2-3 days/week every other day 2-3 days/week Strength Endurance Health F 2-3 days/week every other day 2-3 days/week I 60-80% 1RM 40-60% 1 RM 60-70% 1 RM T 1-3 sets, 1-5 reps 2-5 sets, 15-20 reps 1 set, 8-12 reps T weight training weight training weight training R e 3-5 minutes 1-3 minutes 1-3 minutes s t

Weight Machines vs. Free Weights Resistance is provided by both types. Exercise machines --Safer, convenient, and easy to use Free weights --Require more care, balance, and coordination --Strength transfers to daily activities

Things to Keep in Mind… Too much endurance training can cause a loss of strength and power DOMS Tone – Quackery??? Weight training safety Warm up and cool down Making progress Advanced strength training programs Too much endurance training can cause loss in strength and power --Due to modification of different muscle fibers. DOMS: Occurs at least 24 hours after exercise, microscopic muscle tears, lasts a day or two To avoid: start gradually, warm-up Tone: “Tonus” - Tension developed in muscle due to passive muscle stretch. --Can’t be determined by feeling or looking at muscle / has little or nothing to do with strength. Weight training safety --Use proper lifting techniques, use spotters and collars with free weights, be alert for injuries Warm up and cool down --Warm up prior to each weight training session with a general warm-up and a warm-up for the exercises you will perform --Cool down after weight training, relax for 5-10 minutes, lower your heart rate Making progress --To start: Choose a weight with which you can do 8–12 repetitions with good form --To progress: Add resistance when you can do more than 12 repetitions --Maintain good form at all times --Track your progress Advanced strength training programs --Performing more sets of a smaller number of repetitions with a heavier weight --Cycle training (periodization) by varying type and amount of exercise --Consult a coach certified by the National Strength and Conditioning Association Fahey/Insel/Roth, Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness, Chapter 4 © McGraw-Hill Higher Education

Resistance Training Myths No pain - no gain Makes you “muscle bound” Fat can be converted into muscle Extra muscle turns to fat if not used Has masculinizing effect on women Extra PRO consumption Pain is your body’s way of telling you to slow down or stop. If you lift using the full range of motion, you will not become “muscle bound” Fat and muscle do not change from one to the other. They are two different types of tissue. Muscles can increase/decrease in size, while fat cells can increase/decrease. Women do not have enough testosterone in their systems to gain the muscle mass that men can gain. It is not actually necessary to increase protein intake when training. Most Americans get more protein than they need anyway.

Remember the Exercise Prescription Website for help in designing a program: www.exrx.net

Lecture Summary Differentiate between fast twitch and slow twitch muscle fibers. Define muscular strength and muscular endurance. Explain the three types of muscle contractions. Explain benefits of muscular training and causes of differences in strength. Develop your own opinion on supplements and drugs supported by evidence from the book. State F.I.T.T. principles for muscular strength, muscular endurance, and general muscle fitness (health) and compare to F.I.T.T. principles for other components of fitness. Explain resistance training myths and why they are not true.