Strength training

• What is static strength

  • Force applied against resistance without any movement occurring
  • Change in muscle length = 0
  • Crucifix position on rings
• What is dynamic strength?

  • Force applied against resistance with muscle changing length concentrically/eccentrically. Strength characterised by movement
  • Power=Speed + Strength
  • Phases of triple jump
• What is maximum strength?

  Ability to produce a maximal amount of force in a single muscular contraction 1 Repetition Maximum (1RM)

  Olympic weightlifter doing deadlift or push in rugby scrum
• 1RM exercises


  • Olympic weightlifter doing a deadlift
  • Single throw in judo
  • Push in scrum
• Explosive strength


  Ability to produce a maximal amount of force in one or a series of rapid muscular contractions

  Elastic strength- use of stretch-reflex mechanism
• Exercises/activities requiring explosive strength

  • Gymnast
  • Sprinter
  • Sprinting down wing in rugby
  • Driving for interception in rugby
• Strength endurance


  Ability to sustain repeated muscular contractions over a period of time withstanding fatigue
• Strength endurance activities

  • Rowing
  • Swimming
  • Wrestling
• Factors affecting muscle strength: cross-sectional area, fibre type, gender, age
• Explain how cross-sectional area effect strength?

  Greater cross-sectional area of muscle = greater strength, up to 16-30 N of force per cm² of muscle
• Explain how fibre type effect strength?

  Greater percentage of fast glycolytic and fast oxidative glycolytic (FG+FOG) fibres = greater strength over a short period

  Fast twitch fibres have larger motor neurons forming large motor units with rapid, high force contractions
• Explain how gender effects strength?

  Males have greater strength due to higher muscle mass and cross-sectional area from higher testosterone levels
• Explain how age effects strength?

  Peak strength in females is 16-25 years, in males 18-30 years. Strength development peaks 20-30 years, then declines due to decreased neuromuscular efficiency and muscle mass
• Grip dynamometer test


  1. Adjust grip for hand size

  2. Zero dial and hold dynamometer with straight arm above head

  3. Bring down as they squeeze maximally

  4. 3 attempts for both hands

  5. Results compared to standardised table
• Grip dynamometer test


  • Simple/objective measure
  • Inexpensive
  • High reliability

  
  

  • Only assesses forearm muscles
  • Not sport specific
• 1 Repetition Maximum (1RM) test

  1. Choose a high weight achievable in one rep to isolate a muscle

  2. Increase weight until only 1 max rep can be achieved

  3. Full recovery between reps to prevent fatigue
• 1RM test


  • Direct objective measurement of isotonic max strength
  • Easy and accessible
  • Can test most muscle groups

  
  

  • Difficult to isolate individual muscles
  • Technique error can lead to early fatigue
  • Potential injury risk
• Uk abdomincal curl test

  
  

  1. Perform continuous sit-ups at progressive intensities to exhaustion

  2. Timed to an audio cue

  3. Test ends when subject can't complete two consecutive sit-ups in time or technique deteriorates
• Uk abdominal curl test

  • Can test large groups at same time
  • Simple and cheap
  • Isolates abdominals
  • Valid and reliable

  
  

  • Good technique essential
  • Repeated strain on lower spine
  • Maximal effort limited by motivation, not sport specific
• Vertical jump test

  1. Use wall-mounted vertical jump board or chalked fingers

  2. Bend and swing arms, mark highest point jumped

  3. Difference represents explosive strength
• Vertical jump test

  • Uses formula to convert data to power output estimate
  • Easy to administer
  • Minimal equipment

  
  

  • Not isolated to one muscle group
  • Only estimates explosive leg strength
• Neural adaptations


  • Increased recruitment of motor units and FG/FOG fibres
  • Decreased inhibition of stretch reflex
  • Improved coordination
  • Increased speed, strength and power output
• Muscular adaptation

  Muscular hypertrophy by 20-45%-Muscle hyperplasia (increased number of muscle fibres)=Increased force of contraction

  Increases size of fast-twitch glycolytic (FG) muscle fibres-Explosive training

  Increases size of fast-twitch oxidative glycolytic (FOG) muscle fibres-Strength endurance training

  Increased number and size of contractile proteins (myofibrils)Increased thickness of actin-myosin filaments

  Increased bone density and mass-Leads to increased absorption of calcium and reduced risk of osteoporosis
• Metabolic adaptations

  Anaerobic energy production-Increased ATP, phosphocreatine, and glycogen stores-Increased capacity for alactic energy production= energy for speed power

  Increased enzyme action-Leads to increased efficiency of anaerobic energy production and reduced onset of fatigue

  Increased buffering capacity-Leads to increased tolerance and removal of lactic acid, delayed onset of blood lactate accumulation (OBLA), and increased anaerobic threshold

  Increased muscle mass-Leads to increased metabolic rate and improved body composition
• Strength training guidelines for maximum, explosive and endurance strength


  • Type of strength
  • Intensity: % of one rep max
  • Repetitions
  • Sets
  • Work:relief ratio
  • Recovery between sets
• Maximum strength


  • 85-95% of one rep max
  • 1-5 reps
  • 2-6 sets
  • 1:3+ work:relief ratio
  • 4-5 mins recovery
• Explosive strength


  • 75-85% of one rep max
  • 6-10 reps
  • 4-6 sets
  • 1:3 work:relief ratio
  • 3-5 mins recovery
• Endurance strength (advanced)


  • 50-75% of one rep max
  • 15-20 reps
  • 3-5 sets
  • 1:2 work:relief ratio
  • 30-45 secs recovery
• Endurance strength (basic)


  • 25-50% of one rep max
  • 15-20 reps
  • 4-6 sets
  • 1:2 work:relief ratio
  • 60 secs recovery
• When revising the specific guidelines for developing each type of strength, learn one number and not a range
• Weight training


  • Involves very high resistance, low repetition exercises to increase muscle size and strength
  • Can be used to develop any type of strength by altering intensity as a percentage of one rep max
  • Can be most appropriate for maximum strength
  • Can be specific to a muscle group or joint movement
  • Requires less active muscles to work isometrically as fixators
  • Flexible and can be adjusted for the individual, sport and type of strength required
  • Potentially dangerous and a 'spotter' is often required
• Weight training exercises


  • 3 sets of 4 reps at 90% of one rep max with 5 mins between sets
• Multi-gym


  • Fitness system with multiple components designed to perform a wide range of exercises
  • Each station has an adjustable weight stack which can be easily changed to suit specific strength requirements and training techniques
  • Space efficient, safe and can provide a total body workout
  • Exercises are generic and may not suit specific movement patterns required in some sports
• There are many variations of weight training and the use of a multi-gym from simple sets and pyramid systems to super sets
• Plyometric training


  • Involves a series of explosive exercises to improve the speed at which a muscle shortens
  • Typical exercises include hopping, bounding, jumping and press-ups with claps
  • Benefits explosive strength specifically
  • Important for training sprinters, throwers and jumpers in athletics, as well as racket sports, netball and basketball players
  • Muscles generate greater force of contraction if pre-stretched
  • Takes the muscle through an eccentric contraction before a concentric contraction
  • Eccentric contraction stores elastic energy which is then released to create a more powerful concentric contraction
  • Neuromuscular system is stimulated to adapt, recruiting more motor units, and initiate a stretch reflex
  • Mostly associated with the lower body, but can be modified for the upper body
  • Significant increases in explosive strength can be made, but high risk of injury so should only be used by experienced performers
  • Participants should be screened for injury and exercise-induced muscle damage should be limited by completing a thorough warm-up and active recovery
• Stretch reflex


  A protective mechanism which causes a muscle to concentrically contract in response to being overstretched
• Circuit training


  A series of exercise stations usually arranged in a specific order to work alternate muscle groups
• Circuit training


  • Can involve body weight exercises, multi-gym, free weights or plyometric exercises
  • Very flexible and can be adapted to improve maximum strength, explosive strength or aerobic capacity
  • Can be made very sports-specific by incorporating specific stations
  • Can cater for large numbers at varying levels of fitness
• Interval training


  Similar to circuit training with a relief period between each exercise station
• Variables to manipulate when designing a circuit or interval training session

  • Work intensity (number of circuits, stations, repetitions)
  • Work duration (length of time at each station)
  • Relief interval (length of time, activity between stations)
  • Number of work:relief intervals