How to Train an Athlete's Limiter

Over the last few blog posts, I have outlined how to Complete and Analyze a 5-1-5 Assessment. Briefly, a 5-1-5 assessment consists of progressively harder load steps where 5 minutes of work are followed by 1 minute of complete rest, then repeated. After the load is repeated twice it is increased until the athlete cannot finish a load or has completed sufficient work to gain enough information about their physiology. Using this data one of three major physiological limiters can be identified.

After a limiter is identified it’s important to address that limiter in order to improve/optimize an athlete’s performance. The reason addressing a specific limiter is important is summed up in the following analogy courtesy of Evan Peikon from Training Think Tank. Addressing a limiter is similar to addressing the slowest portion of a car manufacturing process. If engines take the longest time to assemble it doesn’t make sense to attach the bumpers faster. Maximal time savings will occur only if the engine assembly occurs faster. This is why addressing the physiologic limiter should help an athletes’ fitness. In this article I want to outline some sample training approaches/interventions that can be completed in order to boost the three different limiters. The below interventions are suggestions and should be used as supplements (1-2 days per week or shift in training block focus) to a good training plan. As a refresher the three limiters include:

Muscular – Typically occurring in less experienced athletes or those returning from injury this limitation implies that the athletes’ body is capable of delivering more oxygen than the muscle is able to consume.

Intervention: Since a muscular limitation occurs in those who are undertrained or coming back from injury, the simplest intervention is to increase exercise volume and/or intensity slowly to begin to maximize mitochondrial adaptations to exercise which typically take 4+ weeks to translate changes to performance. Primary adaptations to mitochondria are volume and intensity dependent with high-volume lower-intensity exercise resulting primarily in expansion of the mitochondrial reticulum and protein pool (i.e. 60-90 @60% VO2max) whereas high-intensity lower-volume training leads to increases in the mitochondria’s ability to maximally utilize oxygen (i.e. 4x4min as hard as possible 4 min rest).

Cardiac – This limitation implies that the ability of the heart to move adequate amounts of oxygenated blood is insufficient to meet the oxygen demands of the working muscles and organs to support exercise.

Intervention: In order to target a cardiac limitation the exercise the athlete undergoes must allow the heart to reach high heart rates and maximal contractility (stroke volume). This can be accomplished a few ways 1) start workouts out slowly, allowing for the heart to respond to the metabolic demand being placed on the muscles, this is done by slowly increasing the intensity during intervals, and/or 2) focusing on higher volume easier training, where muscle oxygenation is continuously increasing throughout long higher volume workouts.

Pulmonary – This limitation implies that the lungs lack the ability to either 1) load oxygen onto hemoglobin, or 2) adequately exchange CO2 from the body to the environment.

Intervention: Targeting a pulmonary limitation is a bit tricky with standard gym equipment but the goal is to increase breathing rate of the athlete, stressing the inspiratory and expiratory muscles. This can also be accomplished in a number of ways. 1) Sets of resisted breathing, this requires something like a spirotiger or breath training device but can also be accomplished through focusing on proper breathing techniques during high intensity training. Proper breathing technique has the athlete focus on deep diaphragmatic breaths that expand the entire rib cage, NO SHALLOW BREATHING ALLOWED. And/or 2) repeated desaturation training like a Tabata workout (i.e. 8minutes or 16 x 20s (all-out) on/10s off  the athlete should focus on proper breathing technique during the entirety of the 8 minutes of work.

The above should give coaches a starting point to address the limiters that are determined during a 5-1-5 Assessment. Re-assessments should occur every 4-6 weeks to allow the coach to evaluate if their athlete’s limiter is improving or if a new limiter is most limiting to performance. Coaches, if you have experience training limiters please comment below with your best/favorite interventions to address each limiter described above.