Interview – Darryn Willoughby PhD FISSN

SNI: How much creatine is absorbed when you consume let’s say about 5 grams of it?

Darryn: There is an upper limit of muscle creatine content which can be accomplished by taking 3 grams/day of creatine for 30 days. However, after two days of loading (20 grams/day), maximal muscle creatine content occurs, and amounts at this dose beyond this time are unnecessary. Ingesting low doses (1 – 10  grams) of creatine will reach maximum concentration in the blood within 2 hours. In response to a 5 gram dose, the typical maximum absorption is approximately 100 mg, and occurs at 1 hour post-ingestion. This means that out of 5 grams of creatine ingested only about 2% is bioavailable.

SNI: Is an increase in urinary creatinine something that occurs after creatine consumption?

Darryn: Creatine is typically not found in urine since it has the ability to be reabsorbed in the kidneys. However, creatine is non-enzymatically degraded to creatinine, which is excreted in the urine. In the case of creatine over-consumption, as indicated in question #1, excess creatine will be converted to creatinine and released in the urine. Therefore, monitoring urinary creatinine levels can provide a general index of creatine absorption.

SNI:  Creatine consumption activates satellite cells.  What are satellite cells and why is that important?

Darryn: Satellite cells are muscle cells that have yet to fully develop. When they do become activated, they differentiate and then proliferate, not into actual new muscle fibers, but into myotubes where they will donate their nuceli to pre-existing mature muscle fibers. The overall result is that that our muscle fibers will end up with more nuclei, which contains DNA and genes critical to muscle protein synthesis. Heavy resistance training activates satellite cells, but creatine does also. The process of the differentiation phase of satellite cell activation is a highly-ATP dependent process and relies heavily on creatine phosphate. Creatine supplementation can provide the enhanced ability to facilitate the differentiation of activated satellite cells. In the end, this can result in increased muscle mass and performance.

SNI: What is the best form of creatine and why?  Creatine monohydrate?  Cr Nitrate?  CEE?

Darryn: At this point, creatine monohydrate is the best form of creatine. Many of the new form of have absolutely no research data to show their alleged effectiveness. Of the ones that do, such as CEE, the data is clear that creatine monohydrate is superior. The other thing to consider is that with many of these new forms of creatine, such as Cr Nitrate, etc. they are not able to traverse the creatine transporter; therefore, these compounds will most likely be degraded and the creatine molecule released and it absorbed into muscle as with creatine monohydrate. Therefore, in essence these different forms of creatine are no different to creatine monohydrate relative to mechanisms of muscle uptake.

SNI: What are your top 5 supplements for gaining muscle mass and why!?

Darryn:  Here ya go!

1. whey protein: stimulates muscle protein synthesis and minimizes protein damage/degradation

2. creatine monohydrate: stimulate muscle protein accrual through satellite cell activation and increases anaerobic energy and reduces muscle fatigue

3. leucine/BCAAs: stimulates muscle protein synthesis and minimizes protein damage/degradation

4. beta-alanine: stimulates increases in anaerobic energy and reduces muscle fatigue

5. curcumin: little human research yet, but very good rodent data showing this herbal extract to be a very robust anti-oxidant to reduce oxidative stress and local inflammation, thereby reducing the activity of ubiquitin-mediated protein degradation. More human work needs to be done, but I am very confident that this one shows great promise.

Bonus fun question 6.  If you could be a superhero, who would it be and why?

Superman because he possesses great physical strength while being incredibly intelligent, yet at the same time he is very humble, modest, and non-assuming.

BIO – Darryn Willoughby, Ph.D., FISSN holds BS and MEd degrees in Exercise Science from Tarleton State University and a PhD in Neuromuscular Physiology and Biochemistry with a sub-emphasis in Nutritional Biochemistry from Texas A&M University. He is a Fellow of the American College of Sports Medicine and International Society of Sport Nutrition (ISSN). He is also the current President of the International Society of Sports Nutrition, and is a Certified Strength and Conditioning Specialist from the National Strength and Conditioning Association and a certified exercise and sport nutritionist from the ISSN. Dr. Willoughby is an internationally recognized scholar and one of the top leaders in the field where his primary research focuses on the molecular mechanisms regulating muscle hypertrophy and atrophy and the effectiveness and efficacy of nutritional supplements in helping to support muscle hypertrophy, attenuate atrophy, and improve exercise and sport performance. He is well published in scientific research journals such as the Journal of Strength and Conditioning Research, Medicine and Science in Sports and Exercise, Journal of Sport Science and Medicine, and the International Journal of Sports Medicine. Dr. Willoughby gives invited presentations at numerous professional conferences regarding sport performance and muscle adaptation to training and nutritional supplementation.