Category Archives: Diet

Masters Athletes respond to protein intake and resistance exercise as well as young athletes.

CrossFit Masters Athletes and Protein Intake

This is an interesting bit of research.  It was published a year ago but doesn’t seem to have been picked up by news sources.  Here it is: Masters muscles respond to protein intake and resistance exercise by making more muscle as well as young adults.  The study (Patton-Jones et al. 2011) looked at 7 young adults and 7 adults with an average age of 67.  They did multiple reps of knee extensions and ate a meal of lean ground beef.  Its a small number of people, which limits its power, but its hard to recruit people for this kind of thing.  And . . . it required a muscle biopsy.  That might have hurt.  The authors didn’t mention if it did or not.  Thank you study people for doing this for us.

Crossfit Master Amy Kramer of Crossfit Seven,
 Competes in a Reebok CrossFit Fundraiser
at Luke’s Locker, Fort Worth, TX.

Do Masters Athletes need more protein?

This doesn’t mean that there aren’t important differences between people in their 60s and people in their 20s.  See this earlier post.  What the research tells us though is that the rate at which muscle proteins are synthesized following protein intake and resistance training does not appear to change with age.  At least not through our 60s.  The results are important because we all want to stay strong, and most of us would like to get stronger.  That, along with a desire for fun and camaraderie is why we do Crossfit.

Protein Intake and Sarcopenia

It seems like there are a lot of messages out there telling us we won’t be able to.  Stuff it.  Another reason why these results are important is because people tend to lose muscle mass as they age.  This is what sarcopenia is.  It can be a real problem for the elderly, and can severely limit their ability to get around and take care of the business of life.  The question of how much of sarcopenia is inevitable, and how much is due to inactivity hasn’t been completely answered.  But this study points to lack of resistance exercise as a possible major factor.

Symons TB, Sheffield-Moore M, Mamerow MM, Wolfe RR, & Paddon-Jones D (2011). The anabolic response to resistance exercise and a protein-rich meal is not diminished by age. The journal of nutrition, health & aging, 15 (5), 376-81 PMID: 21528164

The very basics of Insulin: what Masters Crossfit and people in general should know.

This post is in response to stuff we overhear, or see repeated on CrossFit affiliate websites, or are told by well-meaning individuals:  The message we keep encountering is that insulin is bad.  A quote that seems to have been copied and pasted to a number of different sites is “insulin makes people sedentary” and it has been attributed to Dr. Robert Lustig.  If he wrote this, it was probably taken out of context and then confused.  That sort of thing happens all the time.  Or there might have been a typo at some point.  (The statement does bring up some thoughts as to how you could test to see if insulin makes people sedentary.  Inject them and see if they decided they’d rather stay home and watch TV or go for a walk?  You might cause their blood sugar to plunge, which might pull the floor out from under them and send them into a coma, but that’s not the same thing as becoming sedentary.  At least not in the context of exercise and fitness.)
Future CrossFit Dude and EMT with his Dad.

Insulin gets sugar out of your blood stream, and keeps it from damaging your blood vessels.  This is important.  If your fat cells are full, or otherwise stressed, they may stop responding to insulin.  They are protecting themselves (Hoehn et al. 2009) possibly at the expense of other types of cells.  The result is that sugar stays in your blood stream. This is what is bad, especially since this can easily become a chronic condition.

Insulin is part of a system that keeps your blood sugar stable.  You want just enough.  Not too much sugar which will cause damage.  Not so little sugar that there will not be enough energy available to keep you walking around.  You need the entire system to function well.  Its system health that matters. Trying to stop one part from doing its job is not going to help.  What you can do to help your body regulate itself, and keep things from spiraling out of control, is to eat well, keep stress at manageable levels, and exercise.   Avoid long periods of sitting too.  You can be a high performer at the gym, but its hard to be active all day long if you have a desk job.  Get up and move around a little, especially after meals (Dunstan et al. 2012).  Even this little bit of effort will help lower blood glucose after a meal, and reduce your body’s need to put out more insulin response (at least in Masters).  You will be keeping your body from having to deal with chronic overloads, which will wear it out (Ceriello et al. 2008), and allow it to keep running the system efficiently.  Again, its the system that matters, not insulin by itself.

Ceriello, A., Esposito, K., Piconi, L., Ihnat, M., Thorpe, J., Testa, R., Boemi, M., & Giugliano, D. (2008). Oscillating Glucose Is More Deleterious to Endothelial Function and Oxidative Stress Than Mean Glucose in Normal and Type 2 Diabetic Patients Diabetes, 57 (5), 1349-1354 DOI: 10.2337/db08-0063

Dunstan, D., Kingwell, B., Larsen, R., Healy, G., Cerin, E., Hamilton, M., Shaw, J., Bertovic, D., Zimmet, P., Salmon, J., & Owen, N. (2012). Breaking Up Prolonged Sitting Reduces Postprandial Glucose and Insulin Responses Diabetes Care, 35 (5), 976-983 DOI: 10.2337/dc11-1931  

Hoehn KL, Salmon AB, Hohnen-Behrens C, Turner N, Hoy AJ, Maghzal GJ, Stocker R, Van Remmen H, Kraegen EW, Cooney GJ, Richardson AR, & James DE (2009). Insulin resistance is a cellular antioxidant defense mechanism. Proceedings of the National Academy of Sciences of the United States of America, 106 (42), 17787-92 PMID: 19805130 ResearchBlogging.org

Diet and protein: training, performance and long-term health.

Protein Intake, training and performance

Diet, protein intake and performance are interwoven issues. The aim of training is improve the body’s ability to perform certain tasks (and in the case of CrossFit it is to achieve a high degree of effectiveness and competence in a wide range of skills and efforts).

Lucas Allen and Summer Rogers at the SouthCentral
Crossfit 2012 Regionals.  Both are in their thirties.

The goal of nutrition in training is to help the body (the entire thing) adapt and remodel, or at least maintain what you have and can do. Bodies like efficiency. Your body will see no point in maintaining bone or muscle that does not look like it’s going to be used any time soon and will let it go. That’s why people who have been ill and disabled for a long time become so frail. When challenged your body (which means here not only muscle and bone, but brain, nerves, biochemical pathways and efficiency, cell proliferation and organelle numbers and function, and neurotransmitters) changes to meet that particular challenge. Protein is important here for repair, strengthen and reinforcement of stressed tissue. Strength-oriented athletes have traditionally made efforts to increase protein intake and there is some evidence that this is effective in increasing muscle mass. There is also evidence that increasing protein intake can reduce the rate of loss of muscle mass seen in aged people.  That’s good for us Masters too.

Cody Zamaripa, age 46, counts burpees during the 2012 Open
at Crossfit Seven, in Fort Worth, TX.

Not all of the protein you can consume will be used to increase mass. Your body will use what it needs, or what it anticipates needing in the near future (in case you persist in doing all those squats, jerks, kettle bell swings and pushups.) Consuming more than you need will probably not hurt you (unless you’ve really gone overboard). Not consuming enough will slow repair and limit your ability to adapt to physiological and mechanical stress.

 Endurance athletes have long been encouraged to eat plenty of carbohydrates since availability of carbs can be a limiting factor in performance. This is why consuming dilute fruit juice (or sugar water) can delay exhaustion and allow an athlete to continue to run, bike or whatever longer than they would if they had been drinking plain water. However if you are always running on carbohydrates you may not adapt biochemically speaking. Normally, if you are low on carbohydrates (or glycogen) your body will attempt to increase the rate at which is uses its own fat stores for energy. Being habitually low on carbs may increase your ability to generate energy by other means. You will probably be uncomfortable for at least a while, but you might improve at this the longer you train.    There are really too many unknowns floating around at present to know exactly what is best.  What is best probably varies by individual, situation, stage of life, and training goals. New information becomes available all the time. We’ll see how things fall out.

Churchward – Venne, T., Burd, N., Phillips, S., & Research Group, E. (2012). Nutritional regulation of muscle protein synthesis with resistance exercise: strategies to enhance anabolism Nutrition & Metabolism, 9 (1) DOI: 10.1186/1743-7075-9-40  

Logan-Sprenger, H., Heigenhauser, G., Killian, K., & Spriet, L. (2012). The effects of dehydration during cycling on skeletal muscle metabolism in females Medicine & Science in Sports & Exercise DOI: 10.1249/MSS.0b013e31825abc7c  

Symonsi, T., Sheffield-Moore, M., Mamerow, M., Wolfe, R., & Paddon-Jones, D. (2010). The anabolic response to resistance exercise and a protein-rich meal is not diminished by age The journal of nutrition, health & aging, 15 (5), 376-381 DOI: 10.1007/s12603-010-0319-z ResearchBlogging.org

Crossfit and the Ketogenic Diet. And a little about Crossfit Vegetarians

Ketogenic diets have proven helpful to people with uncontrolled epilepsy and may be of benefit to epileptics in general, to victims of stroke and other forms of brain injury and possibly cancer. They come with other effects that may not be worth the discomfort or unintended risks to healthy people.

Ketogenic Diets for Healthy People

Some of the problems that may show up along with Ketogenic Diets are kidney stones and, in women and girls, amenorrhea. Amenorrhea is associated with bone loss, increasing risk of osteoporosis, and indicates problems in hormone balance. Supplementation with calcium may help with this, but then again, it might not. Physiology can be quite complex, and consumption does not necessarily indicate absorption is occurring. It is quite possible that something that causes hormonal imbalance in women may also cause hormonal imbalance in men. Playing with one’s physiology, when we don’t know the unintended outcomes of such play, may be inadvisable, especially long-term.

womens shirt crossfit or kettlebell shirt
Birth of Venus and her Kettlebells in Blue: Athletic shirt for crossfit women, kettlebell enthusiasts, and crossfit vegetarians

I have been a vegetarian for 30 years and an athlete all my life. I have excellent bone density, low blood pressure, low resting heart rate, low fasting blood sugar, excellent blood lipid profile and great strength to body weight ratio. I’m happy and healthy, even though I thoroughly understand I represent but a single data point. I do get a lot of advice from well-meaning crossfit friends that I need to eat meat and would be much healthier if I followed a ketogenic diet.  Vegetarians are often described by some Crossfit participants as weak and “skinny-fat”. I will leave it at this: The “optimal diet” for one person may not be the “optimal diet” for another, nor the optimal diet for all conditions. Humans are omnivores and physiologically polymorphic and adaptable. This has given us tremendous abilitity to survive in wildly different climes and environments, and has made us such a resilient species. It is also quite possible, that our individual resilience allows our bodies to adjust to dietary and environmental change.

The current state of research indicates no harm though, from short-term ketogenic diets. I have not found much in the way of research on the risks and benefits of long-term ketogenic diets in healthy adults. Anyone who wishes to add a citation, please feel free.

Kossoff, E., Zupec-Kania, B., & Rho, J. (2009). Ketogenic Diets: An Update for Child Neurologists Journal of Child Neurology, 24 (8), 979-988 DOI: 10.1177/0883073809337162

Bergqvist AG, Chee CM, Lutchka L, Rychik J, & Stallings VA (2003). Selenium deficiency associated with cardiomyopathy: a complication of the ketogenic diet. Epilepsia, 44 (4), 618-20 PMID: 12681013

Brinkworth GD, Buckley JD, Noakes M, Clifton PM, & Wilson CJ (2009). Long-term effects of a very low-carbohydrate diet and a low-fat diet on mood and cognitive function. Archives of internal medicine, 169 (20), 1873-80 PMID: 19901139

A Diet of Animal or Plant Proteins: Which keeps you leaner?

Intake of vegetable protein is negatively correlated with waist circumference and BMI. In contrast, intake of animal protein is positively correlated with waist circumference and BMI, at least in Belgians. There are a lot of questions to raise with this including the possibility that people who eat less animal protein consume less animal fat which can be a rich source of bioactive, lipophilic contaminants which may also be endocrine disruptors that increase adiposity or alter blood lipids. Note Ruzzin et. al.’s April 2010 paper “Persistent Organic Pollutant Exposure Leads to Insulin Resistance Syndrome.” (Very nice work! Congratulations to all authors.) Also possible that people who eat a lot of vegetable protein also eat fewer calories, are less sedentary etc. There is also the argument that lean, grass-fed animals (happy cattle, miserable chickens) would eliminate this vulnerability in meat eaters. That would be an interesting study. BMI and blood lipid profiles in matched cohorts of grass-fed/organic animal protein eaters vs. regular grocery store consumers. Anyone . . . ?
Ruzzin J, Petersen R, Meugnier E, Madsen L, Lock EJ, Lillefosse H, Ma T, Pesenti S, Sonne SB, Marstrand TT, Malde MK, Du ZY, Chavey C, Fajas L, Lundebye AK, Brand CL, Vidal H, Kristiansen K, & Frøyland L (2010). Persistent organic pollutant exposure leads to insulin resistance syndrome. Environmental health perspectives, 118 (4), 465-71 PMID: 20064776Lin, Y., Bolca, S., Vandevijvere, S., De Vriese, S., Mouratidou, T., De Neve, M., Polet, A., Van Oyen, H., Van Camp, J., De Backer, G., De Henauw, S., & Huybrechts, I. (2010). Plant and animal protein intake and its association with overweight and obesity among the Belgian population British Journal of Nutrition, 1-11 DOI: 10.1017/S0007114510004642