Training Strengths vs Training Weaknesses: Applying Liebig’s Law of the Minimum to Athletic Development

Athletic training is often framed as ‘build your strengths and fix your weaknesses’. But in practice, athletes tend to overemphasise one side of this equation, either doubling down on what they are already good at, or endlessly working on weaknesses without improving the qualities that often actually drive their individual performance. A more useful framework comes from an unexpected place - 19th-century agriculture. Liebig’s Law of the Minimum explains how plant growth is limited not by total resources, but by the single most limiting nutrient. This idea translates seemingly well to athletic performance: progress is constrained not by overall fitness, but by the weakest link in the system. However, modern sport science adds an important nuance, while weaknesses often limit performance, strengths are why the high performing individual is a high performing individual. The art of training may actually lie in balancing both.

Liebig’s Law of the Minimum

Liebig’s Law of the Minimum, developed by Justus von Liebig in the 1840s, states that plant growth is determined by the scarcest nutrient resource, not the total abundance of resources. For example, a plant with abundant nitrogen, sunlight, and water but low potassium will still underperform and adding more nitrogen does nothing until potassium is corrected. This principle became foundational in agronomy and systems ecology, where it explains how limiting factors constrain output in complex biological systems. Modern ecological extensions of Liebig’s law suggest that growth is often controlled by multiple interacting constraints rather than a single factor, but the central idea remains powerful, that performance is capped by bottlenecks rather than averages.

Translating Liebig’s Law to Human Performance

Athletic performance is a multi-factor system involving strength, speed, aerobic capacity, technical skill, mobility, recovery capacity and psychological resilience. Just like soil nutrients, these qualities do not contribute equally. Instead, performance is constrained by the weakest or least developed system relative to the demands of the sport. For example, a strong athlete with poor aerobic capacity may fail in repeated sprint sports, a highly conditioned athlete with poor maximal strength may fail in contact or power sports or a technically skilled athlete with poor rate of force development may be ineffective under pressure. This Liebig framework would suggest that performance is limited by the weakest physiological or technical ‘nutrient’. A review in systems physiology highlights how performance emerges from interacting constraints rather than isolated qualities, reinforcing this multi-factor limitation model (Seifert et al. 2014).

Training Weaknesses

Weakness training is the direct application of Liebig’s principle - identify the bottleneck and improve it. Improving the weakest quality often yields the largest performance jump because it may raise the overall system ceiling, improve transfer of existing strengths and reduce performance breakdown under stress. For example, increasing aerobic capacity in a strength athlete improves recovery between sets and training volume tolerance or improving maximal strength in an endurance athlete increases movement efficiency and economy. This aligns with research showing that improving limiting physiological systems produces disproportionate performance benefits, especially in novice to intermediate athletes. However, weakness training has a major drawback, that it may diminish returns at higher levels of performance. At elite levels, weaknesses are less obvious and harder to improve, time spent fixing minor deficits may yield minimal competitive advantage and overemphasis on weaknesses can erode strengths that define performance. Literature would suggest that elite athletes benefit more from targeted development of high-transfer qualities rather than equal distribution across all capacities elite athlete training specificity review.

Training Strengths

If weakness training is about raising the floor, strength training is about raising the ceiling. At elite levels, performance is often determined not by absence of weakness, but by presence of exceptional strengths. For example, sprinters win through maximal acceleration capacity, not general fitness balance, powerlifters win through maximal force output, not aerobic conditioning and endurance athletes win through exceptional aerobic efficiency, not maximal strength. This is consistent with the principle of performance differentiation, where top performers separate themselves through extreme specialization in key traits. Strengths also create cascading adaptations such as high strength improving movement economy, high aerobic capacity improving recovery and training density and high technical skill reducing energy cost of movement. Strengths are therefore not just outputs, but are force multipliers for other qualities. Research in strength and conditioning shows that improvements in primary performance determinants often enhance secondary systems indirectly (e.g., strength improving sprint economy or jump efficiency) (Seifert et al. 2014).

Constraints Change with Training Level

The correct balance between strength and weakness training depends heavily on training status.

Novice athletes: Fixing weaknesses produces rapid gains

• Many systems are underdeveloped

• Weaknesses are large and obvious

• General adaptation is highly responsivez

Intermediate athletes: Mixed model where training address limiting factors, maintains existing strengths and begin specialisation.

• Some qualities are developed, others lag behind

• Trade-offs between strength and conditioning become more relevant

Elite athletes: Strength dominance which is often more productive than chasing minor weaknesses

• Weaknesses are small and resistant to change

• Marginal gains matter more than broad development

• Performance is defined by exceptional strengths

Why Strengths and Weaknesses Are Not Independent

One of the biggest misconceptions in training is that strengths and weaknesses exist in isolation. In reality, they interact. There is a synergistic effect whereby some strengths may improve weaknesses indirectly such as strength training improving running economy, aerobic training improving recovery for strength sessions and mobility improving force expression.

There are also trade-off effects where some adaptations compete. For example excess endurance training potentially reducing maximal hypertrophy and excess strength training potentially reducing endurance efficiency. This interaction is part of the broader concurrent training effect debate, where adaptations compete for physiological resources and signaling pathways.

Practical Application: How to Identify What to Train

Rather than asking whether the athlete should train strengths or weaknesses, instead ask which constraint currently limits the athlete’s performance most.

Step 1: Identify performance bottleneck

• What fails first under competition conditions?

• What limits output under fatigue?

• What differentiates me from better performers?

Step 2: Classification:

• True limiting factor (weakness)

• Performance driver (strength)

• Non-limiting variable (maintenance)

Step 3: Allocation of training time

Although not fixed and adaptive based on season and athlete level, an example distribution model may be:

• Weaknesses / Limiting Factor Training: 40-60%

• Strength Development: 30-40%

• Maintenance and recovery: 10–20%

Case Examples

Example 1: Strength athlete with poor conditioning

• Weakness: aerobic capacity

• Strength: maximal force output

Training priority:

• Improve conditioning (weakness)

• Maintain strength (do not over-reduce heavy lifting)

Example 2: Endurance athlete with low force production

• Weakness: maximal strength

• Strength: aerobic base

Training priority:

• Add strength training (heavy, low volume)

• Maintain endurance volume

Example 3: Team sport athlete

• Multiple interacting constraints: speed endurance, strength, skill under fatigue

Training priority:

This often shifts throughout the season, requiring flexible programming.

Conclusion

Liebig’s Law of the Minimum provides a powerful metaphor for understanding athletic development - performance is limited by the weakest link in the system. Training weaknesses is therefore essential for raising the performance floor. However, sport science also makes it clear that elite performance is defined by exceptional strengths, not balanced averages. Strengths amplify performance, create competitive separation, and often influence multiple downstream systems. The real skill in programming is not choosing between strengths and weaknesses, but instead understanding which constraint currently matters most, and how that constraint changes over time. In early training stages, fix weaknesses, in later stages, protect and amplify strengths while selectively addressing limiting factors. At all stages, remember that performance is a multifactorial outcome, not a sum of isolated qualities.

References

von Liebig J. (1840s). Die organische Chemie in ihrer Anwendung auf Agricultur und Physiologie (Foundational formulation of the Law of the Minimum).

Liebig, J. (1840s). Die organische Chemie in ihrer Anwendung auf Agricultur und Physiologie.

Seifert, L. et al. (2016). Human Movement Science, 48, 132–141.

Suchomel, T. J. et al. (2018). Sports Medicine, 48, 1845–1868.

Issurin, V. B. (2010). Sports Medicine, 40, 189–206.

McGuff, D. et al. (2016). Body by Science.

Joyner, M. J. et al. (2008). The Journal of Physiology, 586, 35–44.