STRENGTH

STRENGTH

1. Strength

   • Grows at the same time as muscle and bones. It is a physical skill which need to be trained.
   • loads
     • Natural load: refers to the weight of one's one body. Overload: it can be the weight of another person or materials.

2. the concept of strengt

   • concept
     • Skill that allows us to overcome resistance or oppose it using muscle contractions.
   • contraction generate tension- resistance
     • strenght>resistance
       • the strenght exceeds the resistance
     • strenght<resistance
       • incapable of overcoming&nbsp;
   • physics terminology
     • F= M x A strength is the product of mass multiplied by aceleration
   • Ways to increase muscular strenght
     • increasing mass or resistance to overcome
     • increasing acceleration of mass
       • &nbsp;This can be done by performing high speed movements.

3. Factors that determine muscular strenght

   • Intrinsic factors
     • Factors originating from inside the body.
     • Neurophysiological factors
       • Factors that affect the ability of the muscle to contract and consequently develop strenght. For example: muscle length or the amount of fibres used.
     • Biomechanical factors
       • They determine the true strength of the muscle and are basically related to the skeletal system of a person.&nbsp; EX: the length of the muscle lever,the angle of traction of the join and the moment of inertia of the load.
     • Emotional factors
       • They can raise the level of strength used to mobilize muscle fibres that are not normally stimulated (normally 60-70%) Ex: motivation, fear or ability
   • Extrinsic factors
     • External factors Ex: food, temperature or training.
     • Evolution of strength with age
       • From 11-16 strength doubles At 16 it reaches 80-85% maximun pick &nbsp;From 20-25% maximun strength is develop. From 30 slow decline. From 50-60 gradual atrophy of mucle develops

4. Types of muscle contraction

   • depends on the resistance that opposes strength.
   • Isotonic contraction
     • When the muscle contracts and causes a change in the length of the muscle fibres.
     • concentric isotonic contraction
       • When muscle length decreases and shortens. Ex: push-ups with dumbbells
     • Eccentric isotonic contraction
       • muscle length increases and becomes longer. Ex: kick a football with your foot.
   • Isometric contraction
     • The strength exerted cannot overcome the resistance and the muscle length does not make any change. Static strength exerted against an immovable resistance. Ex: pushing a Wall.
   • Auxotonic contraction
     • Isotonic and Isometric contractions are produced simultaniously. At the beggining of the contraction, is isotonic contraction and the isometric contraction is highlighted at the end. Ex:&nbsp; stretching an extensor tendom
   • Isokinetic contraction
     • The strength exerted is done at a constant speed,which forces the muscle to work with the same intensity throughout distance. Ex: rowing

5. Types of strength

   • Maximum strength
     • Also kown as slow strength, is the skills of the muscles to develop the highest possible tension. Large loads are mobilised, regardless of the speed. Ex: weightlifting
   • Speed-strength
     • Also called explosive strength it is the strength used by the muscles to give maximum possible speed to a load. The speed of movements is the maximum. Ex: sports that require explosive speed like volleyball or handball.
   • Stamina-strength
     • Skill used by the muscles to withstand fatigue caused by prolonged effort in which many repetitive muscular contractions are performed. Neither the load or speed is maximum so it is a long and continious effort. Ex: swimming

6. Strength training systems

   • Weightlifting
     • Effective system, basically intended to work on maximum strength and mobilise large loads. Can also train other strengths. For doing this you strat with low loads until you reach the maximum weight you can withstand.
   • Isometrics
     • Training system used to work on maximum strength. Based on short durations exercises studied to perform an isometric contraction against immovable resistance. 12- 10 exercises performed in three angles. Used in people who had been injured
   • Isokinetic method
     • Special equipment is used to work on isokinetic contractions. Used to develop maximum and stamina strength.
   • Strength building
     • Develop maximum and speed strength using weight and equipment.
   • Body building
     • Speed strength-training developed in a circuit. 10-12 exercises with 60% loads. Repetitions and recovery
   • Plyometrics
     • Improve explosive strength of the legs. A muscle subjected to an eccentric concentration has greater ability to develop its explosive concentric strength. Jumping repeteadly and more jumping as far as you can.
   • training systems
     • Develop stamina-strength, using loads. Duration from 30-60 minutes, 30 exercises with repetitions and breaks. Produces effects on the body and muscle development.
   • Circuits
     • Develop stamina-strength. Localised excersises are performed using small loads, moderate speed 10-15 repetitions.

7. Training stamina

   • 1 tranning sesion: mantain strength 2-3 training sesions: increase strength 4-5 training sesions: increase stremgth and develop muscle mass.

8. Effects of strength training

   • Hypertrophy: develop muscle mass and increase volume. improve muscle metabolism improve neuromuscular coordination weight gain