Try reading the FAQ

1. How does the training work?
A player needs to reach 100 points in a particular skill to gain a level/point in that skill. Once he gains a level he again starts from 0 plus training points over the 100 from the last level gain.
Each training cycle (once per week) a player gets 10 +- 2 training points automatically, he also gets points from teamwork (teamwork divided by 2), each player also gets gets training points from the coaches skill (For Example: player is training kicking, the coaches skill in kicking is 17 so the player gets additional 17 training points) and lastly he gets 4 additional points for the training hall and 4 for each consecutive training hall upgrade. He also gains/loses points depending on training intensity and players age. And that's the secret of training in Grid-Iron world.
2. How does the training intensity effect the amount of training points received?
Depending on the training intensity you can gain or lose training points and gain or lose fitness (condition). See details below:
Maximum: + 6 training points and - 5 to - 10 fitness points
High: + 2 training points and - 3 to - 6 fitness points
Average: 0 training points and 0 to + 2 fitness points
Low: - 2 training points and + 3 to + 6 fitness points
Very low: - 4 training points and + 5 to + 6 fitness points

Keep also in mind that higher training intensity also means higher chance for players to get injured during the training.
3. How does players age influence the training?
The amount of training points players receive each training cycle steadily decreases after the age of 27 and after the players reach 31 they don't receive any training points at all. This is because they need all the training just to sustain their skills. After the age of 31 the players also start to lose points in their physical skills. See the list below for more info.
- Players aged 16 to 27 train normal and lose no points due to their age.
- Players that are 28 years old lose 25% of their training.
- Players that are 29 years old lose 50% of their training.
- Players that are 30 years old lose 75% of their training.
- Players that are 31 years old get no training points. They also lose from 10 to 15 points on Speed, Strength, Agility and Stamina each training cycle.
- Players that are 32 years old get no training points. They also lose from 16 to 20 points on Speed, Strength, Agility and Stamina each training cycle.
- Players that are 33 years old and above get no training points. They also lose from 21 to 25 points on Speed, Strength, Agility and Stamina each training cycle.
NOTE: No player skill can go below 12 because of his age.
4. How do the training points get distributed among the players skills every training update?
The distribution of points is different for the training regimes as they don't all have the same number of skills that are influenced by the particular training regime.

Training points for attacking training regime are distributed as follows;
40% of all the training points received by the player go to the first randomly selected attacking skill,
25% of all the training points received by the player go to the second randomly selected attacking skill,
15% of all the training points received by the player go to the third randomly selected attacking skill,
12% of all the training points received by the player go to the fourth randomly selected attacking skill
and the last fifth attacking skill gets 8% of all the training points received by the player.

Training points for defending and fitness training regimes are distributed as follows;
50% of all the training points received by the player go to the first randomly selected defensive (if training defence) or fitness (if training fitness) skill
35% of all the training points received by the player go to the second randomly selected defensive (if training defence) or fitness (if training fitness) skill
the last third defensive (if training defence) or fitness (if training fitness) skill gets 15% of all the training points received by the player

Training points for kicking and tactical training regimes are distributed as follows;
65% of all the training points received by the player go to the first randomly selected kicking (if training kicking) or tactical (if training tactical) skill
the last, second kicking (if training kicking) or tactical (if training tactical) skill gets 35% of all the training points received by the player.
5. If I choose “focus on”, does the skill that is selected get all of the available training points?
No. Only a slightly larger percentage of training points will go the the selected skill. Note though that 10% of all the training points goes to waste when using the “focus on” option.

Training regime with 5 skills gets the following distribution of training points;
65% of all the training points go to the selected “focus on” skill, 10% go the the first randomly selected skill and the three other skills get 5% each.

Training regimes with 3 skills get the following distribution of training points;
75% of all the training points go to the selected “focus on” skill, 10% go to a randomly selected skill and 5% go to the last available skill.

Training regimes with 2 skills get the following distribution of training points;
75% of all the training points go to the selected “focus on” skill and 15% go to the other available skill.
6. What about the player's talent. How does that effect the training?
Talent has no direct influence on training as such. It does however limit how high a player can reach in his skills. If a player has talent;
1 then his maximum is 11
2 then his maximum is 12
3 then his maximum is 13
4 then his maximum is 14
5 then his maximum is 15
6 then his maximum is 16
7 then his maximum is 17
8 then his maximum is 18
9 then his maximum is 19
10 then his maximum is 20

The only 3 exceptions to this rule are speed, strength and stamina. Speed and strength are limited by a hidden maximum value (different for each player) that represents the maximum value player can reach even if he trains with weights each and every day. Stamina is not limited at all, and with extensive physical (fittness) training every player can reach 20 in stamina.
7. Is it possible for a player to go above his maximum?
It is possible, it's just that much harder for the player to achieve that.
If a player is at his maximum then he has 1 in 3 chance to gain a point/level.
If a player is at his maximum + 1 then he has 1 in 5 chance to gain a point/level.
If a player is at his maximum + 2 then he has 1 in 10 chance to gain a point/level.
If a player is at his maximum + 3 then he has 1 in 20 chance to gain a point/level.
It is impossible for a player to go more than 4 above his maximum.
8. Does playing games have any effect on player's training?
No. By playing games, the player only increases his overall positional rating (Quarterback, Running back, etc...), which cannot be improved by training alone.