Strength and conditioning? Chapter 4 Training Techniques Minimise the probability of injury Maximise performance Athletic Training Spring 2014 Jihong Park Guidelines Safety: environment, technique, nutrition Warm-up/cool-down Motivation: periodisation, various type of exercises (activities) Overload: greater than normal stress or load on the body is required for training adaptation to take place Weight gain (24yr, 73kg, 177cm, takes 18% protein) EER = 662 (9.53 * AGE) + PA * (15.91 * WT + 539.6 * HT) EER: Estimated Energy Requirement AGE: athlete s age PA: Physical Activity Estimate (very active: 1.48 for men) WT: weight (Kg) HT: height (m) 1 The athlete s daily energy requirement might be 3565Cal. 2 He takes 18% of daily energy from protein: 3565 * 0.18 = 641.7Cal 3 Grams of protein he consumes a day: 641.7/4 = 160.4g 4 Required amount of protein as an endurance or strength athletes: 1.6 * 73 = 116.8g Guidelines Consistency (and regular basis) Progression: gradually increase workloads Intensity: stress the intensity rather than quantity or duration Specificity: strength, power, or endurance? Individuality Minimise stress Enough rest & nutritional support Warm up and cool down A warm-up may injury and performance Whole body activities, stretching, sports specific 10-30 minutes A cool-down period help the body return to resting state (10-15 minutes) Stretching may decrease muscle soreness & stiffness 1
Skeletal muscle contractions Concentric: the muscle shortens in length as a contraction is developed to overcome resistance resistance < muscular force Eccentric: the muscle lengthens while continuing to contract resistance > muscular force Types of muscle activity Isometric: muscle tension is created without changing in the muscle length Ex: therapeutic exercise, trunk muscles Isotonic: lift free weights through full ROM Concentric & eccentric Delayed onset muscle soreness (DOMS) Isokinetic: controlled speed, maximum resistance through ROM Muscular strength The ability of a muscle to generate muscular force against some resistance Neural efficiency (adaptation) # of active motor unit Motor unit firing frequency Motor unit synchronisation Hypertrophy Ex: isometric contraction or 1RM Muscular power Work = Force distance Power = work / time A measure of the work done in a specific amt of time It requires a sudden contraction of muscles to move the body or object in a short amount of time Coordination, efficiency, and timing Ex: vertical jump Muscular endurance The ability to perform repetitive muscular contractions against fatigue for an extended period of time Depends on energy systems available Low intensity with high repetitions Ex: 1 min. push-up, sit-ups, etc. Cardiorespiratory endurance Ability to perform whole-body activities for extended periods of time Maximum aerobic capacity (ml kg -1 min -1 ) The highest rate of oxygen consumption attainable during maximal or exhaustive exercise (Willmore & Costill) The greater the intensity of the performance the greater the O 2 consumption 2
Maximum aerobic capacity Can be increased by conditioning programs Cardiac output (ml/min) = SV X HR Resting CO: approx. 5600 ml/min Periodisation To promote long-term training improvements, the athlete needs to vary training specificity, intensity, and volume in organized planned periods or cycles. Brings peak performance while at the same time reducing injuries and overtraining. Different conditioning needs during different seasons Periodisation Types of muscle fibers Slow-Twitch (type I) Carry more O 2 Fatigue slow (distance running) Long duration aerobic type exercise Fast-Twitch (type IIa & IIb (x)) Capable of producing quick forceful contractions IIa Fatigue moderate (400m) IIb or IIx Fatigue fast (100m) Short-term, high intensity activities IIb I IIa Needs Analysis Analyzing the needs of the activity and the individual athlete involved in that sport What muscle groups need to be trained? What are the basic energy sources? What type of muscle actions/contractions are used? Strength, endurance, or power? Physical demands Sport ATP-PCr Glycolysis/ Oxidative Oxidative Basketball 60 20 20 Golf swing 95 5 0 Gymnastics 80 15 5 Distance running 10 20 70 Soccer 50 20 30 Tennis 70 20 10 Foss & Keteyian (1988) 3
Strength Training: Isotonic Free Weights No restricted motion Iron plates Power exercises Machines One plane movement Relatively safe Simple process to the weight Strength Training: Isokinetic Isokinetic exercise Commonly used in sports medicine clinics to compare between limbs. Reliable, but not valid Objective measurement Not natural motion Research does not support its use Load & volume Training goal Load Goal (% 1RM) repetitions Sets Rest period Strength > 85 < 6-8 2-6 2-5 min Power 75-85 3-5 3-5 2-5 min Hypertrophy 67-85 6-12 3-6 30s-1.5 min Endurance < 65 > 12 2-3 < 30 s Biomechanics of strength Type of contraction External resistance Speed of contraction Force of contraction During rep Between reps Isometric Accommodated None Can vary Vary w/ fatigue Isotonic Constant Vary Must vary Constant Isokinetic Accommodated Constant Can vary Vary w/fatigue Which type of contraction is the best during rehab? - Isometric contraction? - Free weight? - Isokinetic machine? Strength rehabilitation Strength loss following injury due to neural inhibition Decreased # of active motor units Rehab goal is to reverse neural inhibition Inhibited motor units come back on-line Strength rehab By pushing the muscles to contract beyond fatigue in a manner that recruits inhibited motor units (Knight, 2001) Cannot be done isokinetically because resistance decreases as active motor unit fatigue Since isotonic resistance is constant from repetition to repetition, performing repetitions beyond fatigue can only be accomplished if inhibited motor units are activated to take place of fatigued motor units 4
Flexibility It is believed that flexibility is an important component of injury prevention Is flexibility indicative of injury risk? No consensus in the literature A research study (Jones, 1993) suggested that both high and low flexibility were potential risk factors of musculoskeletal injury Flexibility Factors that Limit Flexibility Adipose tissue (aka fat) and skin Muscle length Hypertrophy of the muscles Joint tissue stiffness Nervous tissues Stretching techniques Static stretching Stretch & hold for 3 to 60s Ballistic stretching Bounce Proprioceptive Neuromuscular Facilitation (PNF) Contract-relax, hold-relax, slow-reversal-hold-relax Maybe superior to other stretching methods because of muscular inhibition Neural mobilisation technique Circuit training Lift, move to next station, lift (usually different exercise) Perform multiple exercises during a short amount of time All sets and sessions are timed Work to rest ratio: no rest or 2:1 Progression: #of sets may be optimal Circuit training Another approach to weight training Not a substitute for cardiorespiratory exercise such as jogging or biking Beneficial for beginners, but also a good method for maintaining fitness level throughout the season Can be used for strength, endurance, power, and sports specific Circuit training There is no literature on using circuit training in rehab In a real life setting, clinicians do not often use circuit training in rehab 5
Strength training: Power Sufficient strength required 1RM squat should be 1.5 x body weight. 1RM bench press should be 1 x body weight Strength Training: Power Plyometrics Develop a forceful explosive movement over a shortest amount of time Stretch-shortening cycle Pre-stretching a muscle just prior to a concentric action enhance force production Safety issues Aerobic Training: Interval training Alternating periods of intense work and recovery over a specific distance. Usually stop at a specific time, recovery and go back exercise. Work to rest ratio at 1:1 Train at intensities close to VO 2 max Requires a firm base of aerobic training Recovery from Exercise Cool down with progressively lower intensities Stretch Consume fluids and carbohydrates immediately after exercise Sleep! Ice, massage, anti-inflammatory medications, protein consumption may help or may not AT s Role in Conditioning Work together with coach or strength coach to design optimal programs Prevent injuries & contribute to peak performances ATs are more likely apply it as therapeutic exercise in a rehab program CV training on the 1 st day of rehab Fitness vs. reconditioning 6