Sports Training II: the Motor Abilities, Strength, Endurance, Speed, Flexibility and Coordinative Abilities, with the Characteristics, Types and Determining Factors of Each and the Methods of Developing It

Endurance is the ability to perform movements over a long period without a decline in their efficiency, that is, to resist fatigue. It may be classified by the energy supply as aerobic or anaerobic; by the extent of the musculature involved as local or general; by its relation to the sport as basic (general) endurance, the foundation of all training, and specific endurance for the demands of a particular event; and by its combination with other abilities as speed endurance and strength endurance. By duration, the sports-training literature distinguishes short-term endurance (efforts of roughly 45 seconds to 2 minutes, largely anaerobic), medium-term endurance (roughly 2 to 11 minutes, mixed) and long-term endurance (more than about 11 minutes, predominantly aerobic).

Endurance is determined by VO2max and the capacity of the cardiorespiratory system, the lactate or anaerobic threshold (the fraction of VO2max that can be sustained), movement economy (the oxygen cost of moving at a given speed), the proportion of type I fibres and the muscle's oxidative capacity, energy stores and their use (glycogen and fat), and psychological factors such as willpower and tolerance of discomfort. It is developed by the continuous method (slow and tempo runs), the interval methods, the repetition method, fartlek, cross-training, circuit training for local muscular endurance and, for some athletes, altitude training. A broad base of aerobic endurance is built first, in the general preparatory period, and specific endurance is developed closer to competition.

Speed is the ability to perform movements, or to move from one place to another, in the shortest possible time. The sports-training literature distinguishes several types: reaction ability (the speed of responding to a signal, simple or choice), acceleration ability (reaching maximum speed from a stationary or slow start as quickly as possible), movement speed (the speed of a single movement, such as a punch or a throw, or of movement frequency), locomotor ability (maintaining maximum speed of locomotion, as in the middle of a sprint) and speed endurance (maintaining high speed against fatigue, as in the 200 m and 400 m). Speed is determined largely by heredity: the proportion of fast-twitch fibres, the mobility of the nervous system (the speed of switching between excitation and inhibition), explosive strength, flexibility and elasticity of muscle, technique, the biochemical reserves of the phosphagen system, and concentration and motivation.

Speed is developed by the repetition method: maximal or near-maximal efforts of short duration (typically under about 10 seconds for pure speed) with complete recovery between repetitions so that every run is fast, since training speed while fatigued teaches the athlete to move slowly. Specific methods include reaction drills to varied signals, acceleration runs from different starting positions, flying sprints for maximal speed, resisted runs (sled, slope) and assisted runs (downhill, towing) within limits, and strength and plyometric training for the explosive component; speed endurance is developed by repetitions of longer distances with incomplete recovery. Speed training belongs early in a session, after a thorough warm-up and before fatigue, and the best period for developing it is childhood and early adolescence, when the nervous system is most plastic. Too much speed training of one kind can produce a "speed barrier", a plateau broken by variety.

Flexibility is the ability to execute movements with a large range of motion at a joint or series of joints. Its types are passive flexibility, the range achieved with external help (a partner, gravity or apparatus), which is always greater than active flexibility, the range achieved by the athlete's own muscles; active flexibility may be static (holding a position) or dynamic (moving through the range). It is also classed as general flexibility of the main joints and specific flexibility for a particular sport, such as the hurdler's hips or the swimmer's shoulders. Flexibility is determined by the structure of the joint and its bony limits, the extensibility of muscles, tendons, ligaments and the joint capsule, the strength of the antagonist and agonist muscles, the stretch reflex, age (it declines from childhood), sex (girls and women are generally more flexible), body temperature and warm-up, time of day (greater in the afternoon and evening than on waking), fatigue, and emotional state.

Flexibility is developed by the ballistic method (rhythmic bouncing or swinging movements, which can trigger the stretch reflex and are used cautiously, mainly by trained athletes), the slow-stretch or static method (moving slowly into a stretch and holding it, commonly for about 15–30 seconds, the safest method), dynamic stretching (controlled movements through the full range, now preferred in the warm-up before explosive activity) and proprioceptive neuromuscular facilitation (PNF), such as contract–relax and hold–relax, in which the stretched muscle is contracted against resistance and then stretched further, using the inhibitory reflexes of the Golgi tendon organ and reciprocal inhibition; PNF usually produces the greatest gains. Long static stretching immediately before an explosive event can slightly reduce power, so static stretching is often placed after training or in separate sessions.

Coordinative abilities are the abilities that depend primarily on the processes of motor control and regulation by the central nervous system; they enable an athlete to perform movements precisely, economically and adaptably and to learn new skills quickly. The German school of sports training (Harre, Meinel and Schnabel) lists seven: orientation ability (determining and changing the position of the body in space and time, as a gymnast in the air or a player reading the field); differentiation ability (fine, precise control of force, space and time, as in a drop shot); coupling ability (co-ordinating the movements of body parts into one purposeful action, as in a jump shot); reaction ability (responding quickly and appropriately to a signal); balance ability (maintaining or regaining balance, static and dynamic); rhythm ability (perceiving and reproducing a rhythm, as in hurdling or dance); and adaptation or adjustment ability (changing the movement programme when the situation changes).

Coordinative abilities are determined by the functioning of the central nervous system and the analysers (kinaesthetic, tactile, visual, vestibular and auditory), by the store of movement experience (the more skills learned, the easier new ones become), by the level of the other motor abilities and by age: they develop fastest in later childhood, which is why a varied, multi-sport childhood is the foundation of later skill. They are developed by varying the execution of exercises (speed, rhythm, direction, amplitude), changing external conditions (surfaces, equipment, opponents, fields of different size), combining skills in new ways, practising under time pressure and with restricted or altered information (eyes closed, mirror images, the non-dominant side), and by games and exercises that demand quick decisions. Because they depend on a fresh nervous system, they are trained when the athlete is rested, early in a session.