It is the study of various exercises done to develop sports programmes are divided into three parts :
(1) Preparatory period. (2) Competition period and (3) Transitional period. The concept of sports training refers to the general preparation of a sportsperson to attain high performance through physical, technical, tactical psychological and moral aspects and develop an all round personality so as to make him a good citizen.
Principles of sports training :
The important principles of training are described below :
(i) The Principle of Continuity : According to this principle, the training should be a continuous process. There should not be any break. It should be a regular phenomenon. In fact, there should not be a long period of inactivity. It has been observed that discontinuity of training reduces the physiological capacities of sportspersons. Along this, the interval between two training sessions should be maximum but not too long.
(ii) The Principle of Overload : The principle of overload states that there should be greater than normal load. It means that the training loads should be increased for improving the performance of sportspersons. The normal training load cannot improve the performance. If the training load remains static, the effectiveness of the load diminishes with the passage of time. It can only maintain the achieved adaptation of load. It means that for the continuous improvement of performance, the training load should be increased after the adaptation of previous training load. For example, to increase endurance, muscles must work for a longer period of time than they used to.
(iii) The Principle of Individual Differences :
According to this principle, every sportsperson is different due to individual differences. Each sportsperson’s response to exercise or load will definitely vary. So, a training programme should be modified to take individual differences into the following considerations:
• Large muscles heal slower than smaller muscles.
• Fast twitch muscle fibres recover quicker than slow twitch muscle fibres.
• Woman generally require more recovery time than men.
• Fast or explosive movements require more recovery time than slow movements.
(iv) The Principle of General and Specific Preparation : For the improvement of performance, both the general and specific preparations are equally significant. General preparation serves as the base for specific preparation. As a matter of fact, the performance will be better if the base is better. The general preparation increases the functional capacity of all the body systems and organs and specific preparation is then further required to improve those systems-and organs, on which the performance of sportspersons directly depends. For example, the speed improved through running will also be beneficial in football.
(v) The Principle of Progression: According to this
principle, the overload should not be increased too slowly. If the overload is increased too slowly or if the overload is increased too rapidly, it may result in injury or muscle damage. Exercising above the target zone can be dangerous. The principle of progression also makes us realize the need for proper rest and recovery. The constant overload can lead to exhaustion and injury.
(vi) The Principle of Specificity : This principle states that exercising a certain part or component of the body primarily develops that part. It means that to become better at a particular exercise or skill, we must perform that exercise or skill. For example, a runner should get trained by running, a swimmer by swimming and a cyclist by cycling.

• Kranz anatomy is the special arrangement of the cells found in the C4 plants
• The bundle sheath cells form several layers around the vascular bundles.
• The chloroplasts of bundle sheath cells are large and more in number, they have thick walls and no intercellular spaces.
• Mesophyll cells are undifferentiated and arranged in concentric layers around the vascular bundles.

The questions raised by the first Brandt report was were we to leave our successors with a scorched planet of advancing deserts, impoverished landscapes and ailing environment. The implications of this question are that the current state of the planet is appalling, its vital signs are all indicating towards the fact that its condition doe snot bode well for the future generations. As present inhabitants,we have a duty as stewards of the earth to take responsibility of its welfare and also think about leaving behind a world which is able to sustain our successors. The way in which it is going,this objective seems highly unlikely. However,people still take this matter lightly and this is what needs to change. The question raised by the report is a clarion call to citizens to take action.