Athletes at all levels of competition continue to search intently for nutritional strategies, which may confer athletic performance and recovery benefits. We are operating in an era of unprecedented growth in sports nutrition-related basic, applied and clinical research exploration. Staying abreast of the new and evolving knowledge in performance nutrition can be a daunting task when added to the already overwhelming list of obligations for coaches, trainers, fitness professionals, sports medicine clinicians and athletes alike. The field of sports nutrition involves a complex interplay amongst multiple disciplines that span from applied nutritional biochemistry/integrated metabolism to exercise physiology to psychology.

For this reason, a conceptual framework is helpful for managing and organizing the plethora of advances in performance nutrition science into a context that allows for more effective and practical nutritional program design. The conceptual framework may serve as guidelines for individuals rendering dietary supplement/nutritional advice to athletes. This collection of broad core concepts includes: Rational Poly-supplementation, CHRONO-Nutrition, Restorative Nutrition and Level System of Evidence for Sports Supplements/Nutritional Strategies.

Rational Poly-supplementation

This core concept is akin to the idea of �stacking,� yet it is a broader term which includes integrating nutrients in a coherent fashion so as to amplify the effect of each nutrient on training adaptations. The theory also involves �poly-supplementing� multiple dietary nutrients in a goal-directed manner to yield additive or synergistic ergogenic effects. Rational Poly-supplementation is defined as utilizing two or more nutritional components/metabolites with complimentary mechanisms of action to augment the �effect� and desired response beyond what would be expected with separate mono-supplementation. In this manner, the performance nutrition practitioner avoids redundancy, unnecessary overlap and antagonism that are exemplified with the �everything under the sun� approach.

An analogous approach of strategic stacking has been applied in medicine for decades. Rational �Poly-pharmacy� is an established model of therapy for various disease states, including neuropathic pain, high blood pressure, coronary heart disease, congestive heart failure, diabetes and cancer. In certain cases, multi-targeted and specific drug therapy (Rational Poly-pharmacy) provides optimal disease management, symptom relief, minimized adverse reactions and improved quality of life outcomes.

Human physiology is full of redundant pathways, which are fighting to bring the system back into homeostasis. Oftentimes, to enhance training adaptations, exercise performance capacity and body composition, the system must be challenged from multiple angles in an integrated strategy � hence the term Rational Poly-supplementation.

CHRONO-Nutrition

This is a broad, umbrella term that may be subdivided further into three components, namely, nutrient timing, nutritional periodization and supplement holidays:

1. Nutrient timing refers to providing strategic nutritional support at specific times relative to exercise training, recovery, rest, adaptational curve and natural biorhythms in order to harness physiological windows for amplifying the training effect. In other words, nutrient timing involves taking certain supplements or nutrients in the right amounts at specific times to augment body composition, performance and recovery from exercise and athletic competition.

2. Nutritional periodization involves the concept of tailoring nutritional needs (supplements, macronutrients and energy intake) to specific training cycles throughout the year for optimum health and performance. Adjusting and manipulating macronutrients/supplementation as an athlete modulates their volume, intensity and total training workload is an example of nutritional periodization. For athletes in season-based sports, this tool may relate to different strategies for off-season versus, training camp/pre-season or in-season.

3. Supplement holidays offer a physiologic �respite� to maintain optimal responsiveness to nutrients over time. The time off of certain supplements may allow for re-sensitization of the physiologic systems and biochemical pathways involved in nutrient metabolism. In medicine, drug therapy is often interrupted with a �holiday� to optimize the desired effect, while minimizing risk and adverse effects.

Restorative Supplementation

This technique may be somewhat counter-intuitive to the typical application of CHRONO-Nutrition, but it seems to be very effective in certain athletes/trainees with unique clinical or athletic situations. For example, the overtraining/overreaching athlete and athlete with a musculoskeletal injury seem to benefit from restorative nutrition/supplementation to halt and reverse maladaptive metabolic momentum. With restorative nutrition, unique supplementation and/or hypercaloric microcycling could take place during a period of decreased training demand (recovering from injury or unloading/active rest training block). Athletes with soft-tissue injuries (sprain or strains) may benefit from chondro-restorative and strategic amino acid supplementation as a useful adjunct to complement more traditional medical modalities.

Level System for Safety and Efficacy

An evidence-based �level system� for safety and efficacy is a powerful tool for evaluating treatment options, management, prognosis, and diagnoses of disease. Additionally, a similar model can be applied by exercise physiologists, sports/performance nutritionists, trainers, strength coaches, etc. to serve as a guideline for recommendations regarding nutrition and exercise. Four levels may be used to categorize the merit of nutritional practices and sport supplements based on the strength of research-based evidence, scientific rationale, safety and efficacy.

In conclusion, the core concepts of Rational Poly-supplementation, CHRONO-Nutrition, restorative nutrition and a level system of evidence may provide a useful vessel to navigate in the �sea� of performance nutrition science.

Joseph Jimenez, MD, MBA, CSCS and Hector Lopez, MD, MS(c), CSCS are physicians training in the specialty of physical medicine and rehabilitation. They are co-founders of Physicians Pioneering Performance, LLC, a multi-specialty, interdisciplinary group of like-minded doctors who seek to seamlessly integrate musculoskeletal, spine and sports medicine, optimal aging and rehabilitation with medical and performance nutrition, athletic performance and fitness to accommodate the needs of a diverse population. For more information, please visit www.pppmds.com.