In the world of sports performance, the difference between winning and losing often comes down to one key factor: how well an athlete recovers between intense efforts. Many coaches and athletes fall into the trap of thinking that more work always equals better results. However, one of the most effective training philosophies in the history of strength and conditioning—Charlie Francis’ High-Low Training System—proves that smarter programming is the key to long-term success.
Understanding the High-Low Training System
Imagine your central nervous system (CNS) as a battery. Every time you perform high-intensity activities, you drain that battery. If you don’t give it time to recharge, your ability to produce speed, strength, and power diminishes. This is why some athletes feel strong on Monday but sluggish by midweek—they haven’t allowed their CNS to recover.
Charlie Francis, one of the most influential sprint coaches in history, developed the High-Low system as a way to ensure that athletes maximize their training stimulus while allowing their CNS to recover. The system categorizes training activities into three intensity levels:
- High-Intensity (CNS Demanding)
- Low-Intensity (CNS Recovery)
- Moderate-Intensity (The Gray Zone)
Understanding how to distribute these sessions properly is the key to making consistent progress while reducing the risk of injury.
What Constitutes High, Low, and Moderate Intensity?
High-Intensity Work: The Battery Drainers
High-intensity efforts involve maximum speed, power, or force output and place a significant demand on the CNS. These efforts require at least 48-72 hours of recovery before being repeated.
Examples of High-Intensity Activities:
- Sprints and Bounds (95-100% max effort)
- Explosive Jumps (Depth jumps, hurdle hops, broad jumps)
- Heavy Lifting (Weights above 80% of 1-rep max)
- Explosive Medicine Ball Throws
- Maximal Conditioning or Contact Practices
Since these movements recruit the fastest muscle fibers and require the highest neural drive, they are the most fatiguing. If done too frequently without proper recovery, they can lead to CNS fatigue, performance drops, and increased injury risk.
Low-Intensity Work: The Battery Rechargers
Low-intensity work allows the body and CNS to recover while still promoting useful adaptations like increased capillarization, mitochondrial density, and better muscular coordination.
Examples of Low-Intensity Activities:
- General Physical Preparation (GPP) Circuits
- Weights Under 80% of 1RM (Controlled and submaximal efforts)
- Tempo Runs (65-75% max speed, steady pace)
- Medicine Ball Circuits
- Core Work
- Skill-Based Drills (Unopposed, technical work)
Since these activities do not significantly tax the CNS, they are excellent for improving movement quality, enhancing conditioning, and facilitating active recovery.
Moderate-Intensity Work: The Gray Zone
One of Charlie Francis’ key principles was avoiding moderate-intensity training when developing speed and power athletes. This range (76-94% effort/max speed) is problematic because it creates too much stress to recover from quickly but lacks the intensity to drive real adaptation.
- Too fast to be true recovery, but too slow to improve max speed
- Creates unnecessary residual fatigue
- Can lead to chronic underperformance if used too often
However, moderate-intensity work can still have its place in general conditioning phases, as long as it is programmed correctly and accounted for as a high-intensity stressor.
Benefits of High-Intensity Work
Why is high-intensity work so important?
- Increases Maximum Speed & Power – The fastest athletes aren’t the ones who jog at 80%; they are the ones who train fast and lift heavy (this is relative).
- Develops Neuromuscular Efficiency – High-intensity training forces the brain and body to work together more efficiently, improving coordination and reaction time.
- Improves Strength & Explosiveness – Lifting heavy and jumping explosively trains the nervous system to generate more force in less time.
Benefits of Low-Intensity Work
Many coaches underestimate the power of low-intensity training, but it’s just as crucial as the high-intensity days.
- Aids CNS Recovery – Low-intensity work allows the nervous system to recharge without going into a complete rest state.
- Builds Aerobic Capacity – Even speed and power athletes benefit from a solid aerobic base, which tempo runs and GPP circuits help develop.
- Increases Movement Quality – Low-intensity work helps reinforce proper technique without the fatigue associated with high-intensity efforts.
How to Apply the High-Low System
A well-structured weekly schedule using the High-Low method ensures that athletes recover while still progressing. Here’s an example:
Monday: High (Sprints, Weights >80% 1RM, Explosive Jumps)
Tuesday: Low (Tempo Runs, Med Ball Circuits, Core)
Wednesday: Low (Skill Work, Recovery, GPP Circuits)
Thursday: High (Explosive Jumps, Heavy Weights, Speed Drills)
Friday: Low (Recovery Bike or Swim, Mobility, Core Work)
Saturday: Low (Technical Skills, Tactical Work)
Sunday: Off
By following this format, athletes avoid back-to-back high-intensity days, which can lead to burnout or injury. Instead, the CNS is allowed to fully recharge, meaning that when it’s time to push hard, the athlete is ready to perform at their best.
Stay Tuned for Our Follow-Up Article!
Not all athletes should train the same way. Your athlete’s training age, whether they’re in high school, college, or at an elite level, will determine their training volume and density. In our next article, we’ll break down how the High-Low system is adjusted based on an athlete’s development and competition schedule.
Work with Speed Mechanics to Plan Your Season
At Speed Mechanics, we help teams and coaches integrate team training into practice plans. Our approach ensures that athletes peak for playoffs and key competitions by optimizing their training load throughout the season. Our team training packages include season planning, recovery strategies, and peaking protocols.
Want to take your team’s training to the next level? Contact us today to build a customized High-Low program that fits your team’s needs!