The Most Important Developmental Phases in Youth
Simply put, development from ages 6 to 18 is divided into five phases:
Phase 1: Early Childhood (6-9 Years)
Physical: Steady growth. No hormonal surge.
Cognitive: Concrete thinking. Learning through play.
What makes sense in training: Coordination, joy of play, lots of ball contact. Game-based forms instead of drills.
Phase 2: Later Childhood (9-12 Years)
Physical: Stable growth phase. Highest learning capacity for movements.
Cognitive: Beginning of abstract thinking. Can understand rules, follow instructions.
What makes sense in training: Focus on technique. "Golden learning age." Speed, coordination, all ball techniques.
Phase 3: Puberty (12-15 Years)
Physical: Growth spurts. Different progression in individual children.
Cognitive: Game intelligence develops strongly.
What makes sense in training: Careful load management. Tactical content. Focus on game systems.
Phase 4: Late Puberty (15-17 Years)
Physical: Growth slows down. Muscle building possible.
Cognitive: Adult-like thinking. Self-reflection.
What makes sense in training: First athletic content. Consolidation of game systems. Mental preparation.
Phase 5: Adolescence (17-19 Years)
Physical: Adult level largely reached.
Cognitive: Fully developed.
What makes sense in training: Full training program like adults. Specialization.
What Young Players Are Specifically Allowed to Do at Each Age Level
Here's an overview of what is sensible and safe at each age level:
Bambini (U6-U7)
Technique: All basic ball skills through play
Speed: Very little, integrated into movement games
Endurance: Playful, never long runs
Strength: Bodyweight is sufficient (climbing, obstacles)
Flexibility: Automatically through movement games
Tactics: None
Training Duration: 60-75 minutes max
F-Youth (U8-U9)
Technique: First passing, shooting, receiving exercises
Speed: Short relays, sprints under 5 seconds
Endurance: Game-based forms with breaks
Strength: Bodyweight. No dumbbells.
Flexibility: Playful
Tactics: Simple game-form rules
Training Duration: 75-90 minutes
E-Youth (U10-U11)
Technique: Main focus of this entire phase. "Golden learning age"
Speed: Short sprints (max 6 seconds), acceleration drills
Endurance: Game-based forms, first longer game-form phases
Strength: Bodyweight, obstacle challenges
Flexibility: Coordination stations
Tactics: First 1-on-1 concepts, simple game-based forms
Training Duration: 90 minutes
D-Youth (U12-U13)
Technique: Continued focus
Speed: Sprint intervals (max 8 seconds)
Endurance: Longer game-based forms, first athletic components
Strength: Bodyweight (push-ups, pull-ups, squats). NO dumbbell strength training.
Flexibility: Introduce stretching
Tactics: Game system fundamentals, pressing concepts
Training Duration: 90 minutes
C-Youth (U14-U15)
Technique: Deepening
Speed: Classic interval speed training
Endurance: Game-specific intervals
Strength: Careful introduction to machine training possible (NOT before growth ends). Bodyweight remains the focus.
Flexibility: Systematic stretching
Tactics: Focus on game systems
Training Duration: 90 minutes
B-Youth (U16-U17)
Technique: Match-specific
Speed: Full range of speed training
Endurance: Full, with load intervals
Strength: Strength training possible (with coach supervision)
Flexibility: Systematic
Tactics: Full tactical spectrum
Training Duration: 90-105 minutes
A-Youth (U18-U19)
Technique: Professional level approach
Speed: Full
Endurance: Full
Strength: Full, individually adapted
Flexibility: Full
Tactics: Full
Training Duration: 90-105 minutes
What You Must Consider During Growth Spurts
Growth spurts (mostly between 12 and 15 years) are critical. Bones grow faster than muscles and tendons. Consequences:
Risks during Growth Spurts
- Knee pain (Osgood-Schlatter disease)
- Heel problems (Sever's disease)
- Higher risk of injury with speed-related strain
- Temporary loss of coordination
What You Must Do as a Coach
- Take complaints about knee or heel pain seriously, do not "let them play through it"
- Reduce load if pain occurs
- Plan for recovery phases
- Inform parents about possible symptoms
Signs that a Player is in a Growth Spurt
- Sudden increase in height (often visible during season breaks)
- Worsening coordination ("suddenly seems clumsier")
- Complaints of knee or heel pain
- Fatigue beyond the normal level
During this phase: Adapt load individually. No strenuous sprint or jump loads.
Strength Training in Youth: What's Possible, What's Not
A frequently misunderstood topic. Clear guidelines:
Up to 12 Years
NO systematic strength training with equipment. Bodyweight is sufficient: push-ups, pull-ups, squats, obstacle movements.
Playful exertion in game-based forms is the best strength preparation.
12-14 Years
Careful introduction. Maximum bodyweight plus light objects. NEVER maximal load. NEVER stress growth plates.
14-16 Years
Start of actual strength training possible – but under supervision. Low weights, many repetitions, precise technique. Never maximal load.
16+ Years
Classic strength training possible. With coach supervision. Considering individual maturity.
What ALWAYS Applies to Strength Training
- Warm-up 15 minutes
- Technique before weight
- Clarify breathing technique
- Breaks between sets
- Never train to failure
Endurance Training in Youth
Endurance is important in football, but should be approached differently in youth than in adults.
Up to 12 Years
NO long runs without a ball. Endurance develops from game-based forms. "We're going to run 5 laps now" is incorrect.
12-15 Years
First longer loads, but game-specific. Game-based forms with load intervals. No classic continuous running training.
15+ Years
Classic endurance methods possible. But: Game-specificity remains a priority.
Speed: When What Makes Sense
Speed is crucial in football – but also age-dependent here:
Up to 10 Years
Short, playful sprints. Acceleration drills. Never more than 5-6 seconds of continuous sprinting.
10-12 Years
"Golden age of speed." Sprint intervals possible. Reactive exercises. But: Always with long breaks.
12-15 Years
Be cautious during growth spurts. Otherwise: develop.
15+ Years
Complete speed methodology.
How to Individually Manage Training Load
Not all 14-year-olds are developed equally. Birth month, maturity, and training history all play a role. Three tips:
Tip 1: Take Subjective Feelings Seriously
If a player says "that hurts," believe them. Don't say "don't be a wimp." Growth pains are real.
Tip 2: Visualize Training Load
In Coach OS, you can document training load. If a player had three hard training sessions in a week, the fourth should be light.
Tip 3: Pay Attention to the Season's Progression
A player who had 30 competitive matches in the first half of the season needs to be loaded differently than one with 10 matches.
When a Sports Physician Consultation Makes Sense
In three situations:
Situation 1: Recurring Pain
If a player experiences knee, heel, or back pain for several weeks – a sports physician consultation is recommended.
Situation 2: Sudden Dips in Performance
If someone suddenly performs worse for no apparent reason – a sports physician check-up. Iron deficiency or thyroid problems can also be behind it.
Situation 3: Before Strength Training (from 14 years old)
Before a young person begins strength training, a sports medical check-up should be performed.
What Should NOT Happen in Training
A negative list:
Forbidden Regardless of Age
- Playing with pain that is not "just muscle soreness"
- Punishment sprints ("whoever fouls runs 5 laps")
- Unpunished exertion beyond what is tolerable
- Humiliation as a training motivator
Forbidden for Younger Age Groups
- For Bambini up to E-Youth: long runs
- For Bambini up to E-Youth: strenuous strength training
- For Bambini up to E-Youth: speed loads exceeding 6 seconds
- For Bambini up to E-Youth: maximal exertion in competitive situations
How Coach OS Helps You with Age-Appropriate Planning
Coach OS differentiates exercises by age suitability. If you coach a D-Youth team, you'll receive exercise suggestions appropriate for D-Youth. No athletic content that would be suitable for an A-Youth team.
Specifically:
- Over 1,200 exercises are categorized by age suitability
- AI considers your team's age when suggesting training sessions
- Load profile is adjusted to be age-appropriate
- Game-form sizes and playing distances match the age group
You don't have to figure out what's appropriate for D-Youth yourself – Coach OS suggests it.
Frequently Asked Questions about Load in Youth Football
Conclusion: Age-Appropriate Training is Mandatory – Not a Nice-to-Have
A youth coach who operates without knowledge of growth phases risks injuries and developmental gaps in their players.
You don't need to become a sports scientist. But: Knowing the basic rules, taking pain seriously, managing load appropriately for age, not introducing strength training too early – that's part of the coaching job.
Coach OS supports with age-appropriate exercise suggestions. You don't have to check every exercise for suitability yourself.
[Try Coach OS for age-appropriate training 30 days for free →](https://coach-os.com)
Coach OS is the platform for football training planning. With over 1,200 exercises, categorized by age suitability. From Hamburg.