Can Female Ultra-Endurance Athletes Compete with the Men?

I think anyone in the endurance community has heard this theory before that females may be able to maintain that high intensity of exercise for a very long time...and perhaps even compete with, and beat some of the males.  Especially when you get into ultra-distance events.  More and more females are winning these things.  I received a perfect score on this paper, so I'm hoping I'm on to something here :)  Teacher said she enjoyed  my topic and would love to see more research done in the area!  Hope it helps anyone who reads it!  Ok-here's the paper:

I found it very interesting while reading the chapter titled, “Macronutrient Metabolism in Exercise and Training,” from our book, “Sports and Exercise Nutrition,” to read that trained muscle has an improved ability to catabolize, or breakdown, carbohydrate aerobically for energy use (McArdle, Katch, & Katch, 2009).  This is due to an increased oxidative capacity of the mitochondria and increased glycogen storage.  Trained muscle uses more fat for energy during submaximal exercise, and relies less on muscle glycogen and blood glucose (McArdle, Katch, & Katch, 2009).  Furthermore, when I read the section on gender differences in the training effects of substrate use, I was intrigued by the fact that at an equal percentage of an athlete’s VO2max, such as 80%, the female gender takes a smaller proportion of energy from carbohydrate oxidation than men during submaximal exercise.  After cardiovascular exercise training, women show a greater shift towards fat catabolism, whereas men do not (McArdle, Katch, & Katch, 2009).  This got me to thinking about women endurance athletes, especially female ultrarunners.  Ultrarunning consists of running anything over a marathon distance, from a 50k (31 miles) to a 100 mile race or beyond.  I have heard by many ultrarunner friends, as well as from a few articles over the past couple years about female ultrarunners and how some of them can outrun the men. 

This phenomenon seems to be largely unexplained by science, however, and I was skeptical for the many reasons articles from ultrarunning sources online had given.  I found an article from the magazine, Runners World, titled, “Why Women Rule,” by Lisa JHung.  She states that, “In ultrarunning, not only do women compete on the same course and at the same time as the men, they really compete—and do well—against them” (JHung, 2010).  The article then goes on to talk about some ultrarunning races where certain women have either won, or placed in the top three overall, against both genders.  Lisa Jhung asks the question of what makes it possible, whether physiologically, psychologically, or both, for women to compete at these high levels with the men.  Jason Coop, whom JHung interviewed, is an ultrarunning coach, and thinks that women have an edge in ultrarunning just because of their smaller body size.  As the terrain in the race gets more challenging, the smaller body size of the female runner is a larger benefit.  He says that the more difficult the course is the more of an advantage the female ultrarunner has.  However, Coop states that on the uphills, it may not be a benefit to be a female because their hearts and lungs are smaller in size than the male.  “But the descents—like the 36,000 feet of descending at Hardrock—take less of a toll on a smaller person's body. There's less eccentric work with the legs. Over the course of time, as descents add up that's a huge advantage” (JHung, 2010).  Hardrock is a challenging 100-mile foot race in the mountains of Silverton, Colorado.  Eccentric work is the part of the run cycle in which the controlled muscle lengthens under strain during downhill running; more muscle damage occurs during this phase of running (Eston, Mickleborough, & Baltzopoulos, 1995).  Eccentric work is responsible for a lot of the soreness in runners after a hard workout or race (Eston, Mickleborough, & Baltzopoulos, 1995). 

Coop thinks that women seem to excel the more challenging the race is, like in the Badwater ultramarathon, where temperatures can often reach 120-130 degrees in the desert of Death Valley, California.  He then goes on to explain that there is also a psychological component in women that allows them to have an advantage over men.  Coop states, "But I firmly believe that good women endurance athletes are also psychologically better than good male endurance athletes on the elite side" (JHung, 2010).  A sports psychotherapist, Bruce Gottlieb, agrees with Coop, stating that the perseverance seen in these ultrarunning females may be due to the fact that they often think with greater willpower and persistence, whereas men are more inclined to think in terms of going harder, stronger, and faster (JHung, 2010).  The article then goes on to mention an argument that is often brought up about these ultrarunning women.   This is the thought that females are able to endure the pain of a challenging race for so long just because it is ingrained into their nature due to the ability to give birth.  Whether some of these proposed physiological and psychological explanations are facts or not, I found an article from the Journal of Applied Physiology that may explain why some females can endure such long running events, in terms of substrate use during different exercise intensities. 

In my opinion, Coop’s idea of women seeming to excel over the course of a race the more challenging it is, is due to more of a physiological explanation (although I do not personally disagree with the proposed psychological explanations).  In accordance with our book, this study found that maximal fat oxidation was significantly greater in women than in men, with men showing lower rates of fat oxidation and a greater shift towards using carbohydrate as the primary fuel earlier in their workout.  The primary fuels, carbohydrate and fat, oxidized by the muscle to produce energy when an individual exercises, is a widely known concept (Venables, Achten, & Jeukendrup, 2004).  This can be influenced by the amount of glycogen in the muscle, one’s diet, intensity and duration of exercise, and fitness level.  The article does say that there is still some debate on whether sex differences in fat oxidation exists.  Many studies have shown that fat breakdown (oxidation) in the female sex plays a greater role in oxidative metabolism than men (Venables, Achten, & Jeukendrup, 2004). 

Venables, Achten, & Jeukendrup (2004), gathered 300 volunteers (143 females and 157 males) to participate in their study to assess which substrate was being used during a maximal oxygen consumption test to exhaustion.  The test consisted of participants jogging or running on a treadmill, in which the percent grade and speed were increased every few minutes.  During this time, substrate (carbohydrate and fat) use was measured through indirect calorimetry, which uses a metabolic cart to measure oxygen consumption and carbon dioxide breathed out.  For each participant, the maximal fat oxidation and corresponding intensity at which maximal fat oxidation appeared was measured.  On average, maximal fat oxidation was seen at 48+/- 1% of VO2max, which corresponded to exercising at 62+/- 1% of maximal heart rate.  At about 62% of an individual’s maximum heart rate is when the substrate use transitions over from fat use to mostly carbohydrate use to fuel the working muscles (Venables, Achten, & Jeukendrup, 2004).  When exercise intensity was increased even more, a greater decrease in fat oxidation occurred, at about 84% of VO2max and 89% of maximal heart rate, and a RER (respiratory exchange ratio) value of 1 was reached, meaning the exercising individual was burning mainly carbohydrates (Venables, Achten, & Jeukendrup, 2004). 

In contrast with the women, however, the men who participated in the study burned significantly less fat and notably more carbohydrates.  This is due to their greater fat-free mass and lesser body fat mass as opposed to women (Venables, Achten, & Jeukendrup, 2004).  What I found interesting was that the exercise intensity at which maximal fat oxidation was observed was considerably lower in the males than the females.  “When the oxidation data were expressed as a percentage of total energy expenditure, the contribution of fat oxidation to total energy expenditure was greater in women than the men with a concomitant lower contribution of CHO oxidation to total.  This effect was equal across all exercise intensities” (Venables, Achten, & Jeukendrup, 2004).  What this means is that at any given exercise intensity, women actually use more energy fuel from fat than carbohydrates, whereas men use more carbohydrates for fuel rather than fat.  However, females are still burning more carbohydrates at a high intensity of exercise than fat, but what this article and our book is showing is that they actually are able to burn a greater amount of fat  than men even at higher intensities.  This means that for a long endurance event, the exercising female is able to hold off on depleting their glycogen stores; they use more energy from fat metabolism for a longer period of time than males. 

However, this study did not control for menstrual phase or diet, so it really is unknown how much of the discrepancy in fat oxidation contributes to these elements.  Even though there are studies that found the menstrual phase and oral contraceptives both do not contribute to fat oxidation during moderate-intensity exercise, some studies have found conflicting evidence (Venables, Achten, & Jeukendrup, 2004).  Nevertheless, this study has shown that even though those elements were not controlled for, during exercise, there are sex differences in the type of fuel being burned.  “Also, it is highly likely that a degree of the variation found in fat oxidation could be accounted for by diet because it has been shown that altering the diet, either to a high fat/low-CHO or low-fat/high-CHO diet, can increase or decrease fat oxidation, respectively” (Venables, Achten, & Jeukendrup, 2004).  This also means that as the more trained the individual is to exercise at these moderate and higher intensities for a long duration, the more efficient they are going to be at using fat or carbohydrates for fuel during a certain exercise intensity, whether male or female.  However, the female gender is able to hold off carbohydrate oxidation for a longer period of time.  From reading and learning all of this, I am going to assume that some of these female ultrarunners who can run for so long and beat the men, or come close to it, eat a higher fat diet so they can spare their muscle glycogen for later use when they have burned through all of their fat stores for energy use.  Women have also benefited from the training factor, in which trained muscle uses more fat from energy during submaximal exercise (such as running a very long run).  Men can do this, as well, however not to the same extent as women, as shown by this study and previous literature.  Perhaps this is why some female ultra-distance runners have an advantage over the men. 

In conclusion, this study says that when maximal fat oxidation was corrected for fat-free mass in both genders (since some women have less fat relative to their body weight than their higher fat counterparts), a fraction of the inconsistency across individuals may be due to training status and sex, but not percent body fat.  “Although gender accounts for only a small fraction of the observed total variability in fat oxidation, it is apparent from this study that a gender dimorphism does exist in that women have higher maximal rates of fat oxidation and that lipid remains the dominant fuel at higher exercise intensities than in the men” (Venables, Achten, & Jeukendrup, 2004).  Lastly, the article states that in this study, the explanation for many of the differences across individuals in substrate use at a given exercise intensity cannot be rationalized with the variables that were tested (Venables, Achten, & Jeukendrup, 2004).  One other article I found stated this, “A recent study, however, once again suggests that women may in fact have some way, not yet understood, to burn fatty acids better than men do.  If that’s the case, and you combine that ability with women’s greater body fat reserves, the implications are obvious. If some glycogen-sparing goes on along the way, women might be able to get more out of that premium fuel than men do” (Donaldson, 2011).  More research needs to be done in order to figure out what factors across both genders contribute to an increase in fat oxidation, which could be due to hormones or body fat percentage.  We do know this, however:  women can use more energy from fat metabolism for a greater period of time, sparing muscle glycogen across a long endurance race, which may give them an advantage. 

References

Donaldson, Jamie.  (2011).  The secret feminism of “Born to Run” pt. 1: women and

            ultrarunning.  Retrieved from

            http://fitandfeminist.wordpress.com/2011/09/01/the-secret-feminism-of-born-to-run-pt-1-

            women-and-ultrarunning/

Eston, R. G., Mickleborough, J., & Baltzopoulos, V.  (1995).  Eccentric activation and muscle

            damage: biomechanical and physiological considerations during downhill running. 

            British Journal of Sports Medicine.  29, 89-94. 

JHung, Lisa.  (2010).  Why women rule:  In the sport of ultrarunning, women compete shoulder-

            to-shoulder with the men, and sometimes beat them to the finish line.  Retrieved from

            http://www.runnersworld.com/cda/microsite/article/0,8029,s6-238-511--13593-2-1-

            2,00.html

McArdle, W. D., Katch, F. I., & Katch, V. L.  (2009).  Sports and exercise nutrition.  (3^rd ed.).

            Batimore, MD:  Lippincott Williams & Wilkins. 

           

High-fat versus low fat diets for endurance training and exercise performance

 Assignment for class:

I found the section in our book labeled "High-fat versus low fat diets for endurance training and exercise performance" interesting.  Supporters of the high-fat diet for endurance athletes say that an increase in fat intake overtime will encourage the burning of lipids by increasing the capacity mobilize and breakdown fat (1).  In a study done on two groups of males who had the same fitness status, one group was fed a high-carbohydrate diet (65% calories from carbs), and the other group was fed a high-fat diet (62% of total calories from fat).  Both groups exercised 3 days a week at 50-85% of their VO2max (aerobic capacity), for 60-70 minutes during the first 3 weeks, and 4 days a week during the last few weeks.  What the study found was that there was an increase in endurance capacity for those who consumed the high-fat diet (115%), however, the high-carbohydrate group was able to increase their endurance substantially (194%) (1).

Also, our book states that, "Comprised training capacity and symptoms of lethargy, increased fatigue, and higher ratings of perceived exertion usually accompany exercise when subsisting on a high-fat diet" (1).  It is important to remember that there negative health hazards associated with a high-fat diet.  What I found interesting, though, was that this risk may not be a hazard for athletes who burn a ton of calories each day (like endurance athletes), and consume a higher-fat diet (around 50% calories from fat, not the 62% like in the study).  This will NOT increase the risk for heart disease or elevated cholesterol levels, if the athlete maintains a healthy or stable body weight and is able to burn many calories each day (1).

Also, our book states that, "Conversely, significant restriction of dietary fat intake below recommended levels also impairs endurance performance" (1).  So, I think it's very important that athletes recognize this, especially if they are burning a lot of calories each day through training.  They NEED fat, and cannot limit it to dangerously low levels because they will NOT be able to give 100% in each workout or race.  They are still going to have great numbers for blood lipid profiles, triglycerides, etc., as long as they're burning enough calories each day.  I think it's out job to help people understand this.  There is so much junk out there in the media!
1.  McArdle, W. D., Katch, F. I., & Katch, V. L.  (2009).  Sports and exercise nutrition.  (3^rd ed.).
            Batimore, MD:  Lippincott Williams & Wilkins. 

The Negative Effects of a Low-Carb Diet.

I received a perfect score on this paper in Sports Nutrition, so I guess that means it's legitimate?  I don't fool people on health advice and always try to get the truth out to you :)  I really want people to know the truth.  There's a lot of crap out there.

     There are many diets in the diet industry that focus on low carbohydrate intake along with higher intakes of protein and fat.  According to what I have learned through science and the nutrition classes I have taken, the human body needs carbohydrates for it to function normally.  Also, eating higher than average intakes of protein and fat can have potential negative effects on the body (Tapper-Gardzina, Cotugna, & Vickery, 2002).  While searching for articles for this assignment that included misinformation on nutrition, I came across an article from Bodybuilding.com where people wanted to decrease carbohydrate intake to lose weight, but increase energy levels.  This did not make any sense to me, nor have any low-carbohydrate diets that I have read about in the past.  As an endurance athlete, I know how very important carbohydrates are in the diet, particularly complex carbohydrates.  However, just because the endurance athlete population needs carbohydrates to fuel their workouts, this does not mean that sedentary people or people who just strength train do not need carbohydrates for energy.  It does not make sense to eat hardly any carbohydrates in order to lose weight, when they are one of the macronutrients that systems of the body need to function correctly. 

            The article I found from Bodybuilding.com promotes a low-carbohydrate diet in order to lose weight and fat to make visible every muscle on the human body.  The name of the article is titled, “How Can I Increase Energy While Depleting my Carbs?” (Obadike, 2011).  The article states that in order to keep energy levels high, an individual must increase their fat and protein intake.  However, a scientific journal, The Nurse Practitioner, posted an article that states that this type of diet, a high-protein intake with low-carbohydrate consumption worries scientists because all of these diets encourage higher than normal values for protein.  They forbid followers to avoid foods containing higher amounts of carbohydrates (Tapper-Gardzina, Cotugna, & Vickery, 2002).  The diet from Bodybuilding.com wants the individual trying to lose weight to only eat carbohydrates around the time they are going to exercise, because if they eat carbohydrates anytime else during the day, they will store this nutrient as fat and not burn off the additional energy (Obadike, 2011).  Furthermore, since this diet wants their dieters to take in a low amount of carbohydrates when they are not exercising, they are just eating protein and fat the rest of the day (Obadike, 2011).  In my opinion, this will lead to boredom and cravings for carbohydrates because depending on how much activity level is performed, the body will favor carbohydrates.  “Carboydrate is the body’s preferred source of energy, and the body will revert to gluconeogenesis when carbohydrate intake is limited” (Tapper-Gardzina, Cotugna, & Vickery, 2002).  In the end, this diet will probably fail and followers will gain all the weight they lost back from reducing their carbohydrate intake.

            One more point this article made that I did not approve of was the fact that it was telling the dieters to reduce their aerobic exercise in order to conserve energy.  “You also may want to minimize your weekly cardio when depleting carbs in order to save the minimal energy you do have” (Obadike, 2011).  This is not going to work because it is proven that carbohydrates and aerobic exercise both increase energy levels (Tapper-Gardzina, Cotugna, & Vickery, 2002).  However, the article says that adding in more protein and fat will increase energy levels.  “Increase your protein and fat intake by 10 to 15 percent.  This will help give you more energy during your carb-depletion days.  Reduce your daily cardio to help you conserve energy.  Rotate your carbs intake to coincide with your highest physical activity level, which is probably your daily workout” (Obadike, 2011).  Lastly, the article claims that if people closely adhere to these rules, they will have more energy than anticipated while minimizing carbohydrates (Obadike, 2011).

            Just like any diet, though, this low-carbohydrate, high-protein diet will be unsuccessful.  “Researchers have estimated that 80% to 85% of dieters who lose weight will gain it back within 1 to 5 years.  Diets may fail because they restrict both the type and quantity of food, or require dieters to purchase special food” (Tapper-Gardzina, Cotugna, & Vickery, 2002).  These types of diets say that hunger is diminished since calories from fat and protein are not taken into account and dieters can eat as much food containing these nutrients as they want, as long as they are limiting carbohydrates (Tapper-Gardzina, Cotugna, & Vickery, 2002).  This puts the body into starvation mode.  According to the United States Department of Agriculture’s Dietary Guidelines and the Food Guide Pyramid, 275 grams of carbohydrate need to be eaten in a 2000 kcal diet.  In contrast, only 20 to 90 grams of carbohydrate are recommended in the usual low-carbohydrate, high-protein diet.  This is almost like putting the body in a state of starvation because glucose concentrations are decreased from low-carbohydrate consumption, which results in a condition called ketosis.  This circumstance is where the body uses energy from ketosis instead of carbohydrates by making ketones from fatty acids.  Ketosis can cause muscle breakdown,  producing more ketones if protein intake is very high (Tapper-Gardzina, Cotugna, & Vickery, 2002). 

            There is a lot of information from popular sources that say Americans consume too much sugar, which is what these high-protein, low-carbohydrate diets declare.  However, of total calories consumed, Americans closely met the proposed amount of keeping sugar consumption under ten percent (Tapper-Gardzina, Cotugna, & Vickery, 2002).  It is not really the carbohydrate consumption that is making America fat, but the amount of fat intake which leads to obesity.  “Researchers have shown a direct relationship between fat intake and obesity” (Tapper-Gardzina, Cotugna, & Vickery, 2002).  Interestingly, insulin resistance is brought on by old age, a sedentary lifestyle, obesity, high cholesterol, high-fat diets, and impaired glucose tolerance, not a greater intake of carbohydrates, which is what most of these high-protein, low-carbohydrate diets claim (Tapper-Gardzina, Cotugna, & Vickery, 2002).  Furthermore, studies have shown that an elevated consumption of saturated fat can cause insulin resistance, and a high ratio of omega-6 to omega-3 fatty acids will cause an increase in body weight along with increased fasting insulin levels in people with normal blood sugar (Storlien, Baur, Kriketos et. al., 1996).   It seems that every macronutrient and type of food in moderation will help individuals keep a healthy body weight.  “Weight loss from any type of diet will improve insulin sensitivity.  Although calorie restriction and exercise can increase weight loss, changes in macronutrient balance don’t appear to influence insulin action or promote weight loss” (Tapper-Gardzina, Cotugna, & Vickery, 2002).  The total amount of calories consumed, and not limiting certain macronutrients, is very important when one is trying to lose weight.    

            Some negative factors of the high-protein and fat, low-carbohydrate diet include elevated low-density lipoprotein and total cholesterol, which will increase one’s risk of developing coronary artery disease.  Also, other chronic illnesses and cancers can develop from eating a high fat diet (Tapper-Gardzina, Cotugna, & Vickery, 2002).  One study that looked at a high-protein diet over a year used ten individuals to show that low-density lipoprotein, very low-density lipoprotein, total cholesterol, high-density lipoprotein, fibrinogen, and triglyceride profiles all became worse.  Also, C-reactive protein was elevated, which leads to more inflammation in the body (Fleming, 2000).  Additionally, when consuming a high-protein diet, as much as fifty percent of calcium is lost in the urine, which may predispose individuals to developing osteoporosis earlier (Tapper-Garlick, Nurlan, & Patlak, 1999).  Elevated calcium losses in the urine can cause bone resportion, along with no bone formation (Kerstetter, Mitnick, Gundberg et. al., 1999).  In a study done on teenagers who were on a high-protein, low-carbohydrate diet to promote weight loss over the course of three months, researchers found that even while taking supplements for calcium and vitamin D, bone mineral density was drastically reduced.  However, when these individuals returned to eating a normal amount of carbohydrates, they did not excrete a significant amount of calcium in the urine (Willi, Oexmann, Wright et. al., 1998). 

            While on a high-protein, high-fat, low-carboyhydrate diet, most of the weight loss is due to water, not fat.  “Diuresis, caused by low-carbohydrate intake and its effects on sodium loss, water loss, and glycogen depletion, is the primary reason for initial rapid weight loss on the LC-HP diet.  Severely restricting carbohydrate also suppresses appetite, likely due to nausea from sodium loss” (Tapper-Gardzina, Cotugna, & Vickery, 2002).  Also, the LC-HP (low-carbohydrate, high-protein) diet does not contain enough fiber.  Fiber is shown to reduce total and low-density lipoprotein, along with regulating the digestive system.  Fiber decreases the risk of some cancers, diabetes, stroke, obesity, and diverticular disease (Tapper-Gardzina, Cotugna, & Vickery, 2002).  “Researchers believe that the soluble fiber found in fruits and vegetables, oat bran, and legumes, interferes with the absorption of bile acids, thereby lowering cholesterol levels in the blood and reducing the risk of myocardial infarction.  Fiber also lowers insulin secretion after a meal by slowing nutrient absorption” (Tapper-Gardzina, Cotugna, & Vickery, 2002). 

            When individuals seeking to lose weight try a low-carbohydrate, high-fat and protein diet, they are missing certain nutrients they need in their diet to function properly, such as vitamins, minerals, and fiber.  Eating these three essential nutrients will aid in warding off diseases of all kinds (Tapper-Gardzina, Cotugna, & Vickery, 2002).  Also, it is very important to eat every food in moderation, and when trying to lose weight, eat 300 to 500 calories less per day, as well as exercise regularly.  The amount of aerobic exercise an individual takes part in can also help protect the body against chronic diseases, while lowing cholesterol, triglycerides, resting heart rate and blood pressure, as well as improving sleep patterns and energy levels (Cooper, 2010). 

 

References

Cooper, K.  (2010).  The benefits of exercise in promoting long and healthy lives-my

            observation.  Methodist DeBakey Cardiovascular Journal, 4, 10-12.

Fleming, R. M.  (2000).  The effect of high-protein diets on coronary blood flow.  Angiology,

            51, 817-826.

Garlick, P. J., Nurlan, M. A., & Patlak, C. S.  (1999).  Adaptation of protein metabolism in

            relation to limits to high dietary protein intake.  European Journal of Clinical Nutrtition,

            53, S34-S43. 

Kerstetter, J. E., Mitnick, M. E., Gundberg, C. M. et. al.  (1999).  Changes in bone turnover in

            young women consuming different levels of dietary protein.  Journal of Clinical

            Endocrinology & Metabolism, 84, 1052-1055. 

Obi, Obadike.  (2011).  How can I increase energy while depleting my carbs?  Retrieved from

            http://www.bodybuilding.com/fun/ask-the-ripped-dude-more-energy-while-depleting-

            carbs.html

Storlien, L. H., Baur, L. A., Kriketos, A. D., et al.  (1996).  Dietary fats and insulin action.

            Diabetologia, 39, 621-631.

Tapper-Gardzina, Y., Cotugna, N., & Vickery, C. E.  (2002).  Should you recommend a low-

            carb, high-protein diet?  The Nurse Practitioner, 27, 52-59.

Willi, S. M., Oexmann, M. J., Wright, N. M. et. al.  (1998).  The effects of a high-protein,

            low-fat ketogenic diet on adolescents with morbid obesity:  Body composition, blood

            chemistries, and sleep abnormalities.  Pedriatrics, 101, 61-67.

           

Gender Differences in Carb/Fat use During Endurance Exercise...Females may have an Advantage..

I'm just going to quote my sports nutrition book here:

"Available data support the notion of gender differences in carbohydrate metabolism in exercise.  During submaximal (steady state) exercise at equivalent percentages of VO2max (or same relative workload), women derive a SMALLER proportion of total energy from carbohydrate metabolism than men.  This gender difference in substrate oxidation does not persist into recovery."  Interesting.  So, women rely more on fat than tap into their carb stores than men, which is why females may be able to run/bike/swim longer, in GENERAL, not everyone.  And, especially once you start getting into very long distances.

And looking into the physiology further..." With similar endurance-training protocols, both women and men show a decrease in glucose flux for a given submaximal power output.  But at the same relative workload after training, women display an exaggerated shift toward FAT catabolism (fat breakdown), whereas men do NOT.  This suggests that endurance training induces greater glycogen-sparing at a given relative submaximal exercise intensity for women than for men.  This gender difference in substrate metabolism's response to training may reflect differences in sympathetic nervous system adaptation to regular exercise (i.e. a more blunted cholamine response for women).  The sex hormones estrogen and progesterone may affect metabolic mixture indirectly via interactions with the catecholamines or directly by augmenting lipolysis (fat breakdown) or glycolysis (carb break down).  Five potential sites for endocrine regulation of a substrate (fat/carbs) use include:

1.  Substrate availability (via effects on nutrient storage)
2.  Substrate mobilization from body tissue stores
3.  Substrate uptake at tissue site of use
4.  Substrate uptake within tissue itself
5.  Substrate trafficking among storage, oxidation, recycling

Any glycogen-sparing metabolic adaptations to training could benefit a woman's performance during high-intensity endurance competition."

Wow, cool!  So, men are more powerful and stronger than women, but it seems women can last longer when it comes to endurance events, especially ultra's.  I have been searching around for research to back up that theory I have been reading about over the course of 2 years. 

From the book Sports and Exercise Nutrition by William D. McArdle, Frank L. Katch, and Victor L. Katch.

Obesity in America

Happy New Year!  I guess the focus of this blog is again, health and fitness.  That's right.  HEALTH AND FITNESS.  Not trying to fit into an ideal body image, no diet advice, and I'm going to try to not talk about myself in this blog (maybe a little, haha)

So, I just finished reading this interesting book that has changed my thinking about the "Obesity Epidemic" in America.  Now, within my major, I have learned about 3 different bodies types-the ectomorph (thin, lean, light muscles, hard to gain weight), the mesomorph (gain muscle easily, athletic, muscular, hour glass body shape), which, I think mostly describes my body haha, and the 3rd, endomorph (more stockier, also gains muscle easily, maybe softer skin in terms of thickness).  Or perhaps I'm a combination of all 3, who knows.  Take a look at this website-it's legit.  http://www.bodybuildingpro.com/bodytypeinformation.html

So, now that we know the 3 body shapes, it is very hard for one to change that body shape.  Which, I believe, is why some people are better runners, swimmers, cyclists, weight lifters, etc.  The book I read is called "The Obesity Myth," by Paul Campos.  He had a number of good arguments that the fear of getting fat is hazardous to your health.  For 1, those BMI tables?  No scientific value whatsoever.  You can still be fit and "fat" with a BMI of 28.  Heck, someone of 130 lbs and 170 lbs at 5'5" can be the same in terms of health.  As long as your triglycerides, cholesterol, blood pressure, heart rate, and all that stuff your doctor tests for each year are within the normal range, folks :)  It's the truth.

Of course, it's also bad for health to be thin, or fat, or at any weight, actually, if you do NOT eat healthy and do NOT exercise.  In other words, like I said, you can be thin, average, or bigger, but still be healthy and fit, hence the 3 different body types :)

What has America done?  We label foods as "good" or "bad."  We constantly limit ourselves, try the newest and greatest weight loss drug, constantly cut calories or fat.  Well, guess, what, we NEED fat.  Not the fat in processed foods, fast foods, convenient foods, etc, but the fat in almonds, walnuts, peanuts, avocados, meat, oh and sugar?  Not so bad, as long as we don't over do it.  So go ahead and eat some ice cream, as well.  Eat when you're hungry, stop when you're full, don't deny yourself your favorites foods or you'll go crazy and binge later-not good for health.  Did you know the French have the highest fat diet, yet they are the slimmest?  That's because they know how to eat in moderation, eat 5-6x a day, and get the satiety they actually need from foods.

Low fat and fat free?  Those foods often have additives, preservatives, chemicals, etc that our bodies do not need, and probably don't know how to process, making us gain unnecessary weight, or worse, develop some sort of disease that maybe we carry the gene for, but would have never turned the gene on had we been eating a healthful diet in the 1st place and exercising.

Now, I have been a culprit of that thinking.  Yep.  I would recommend this book to anyone.  Helped give me a better idea of what's going on in the food, diet, and weight loss industry.  Now, I have never taken any diet pills, have always believed to keep healthy from good eating and exercise, but if I ever considered diet pills (which I have not-why would u waste $ on something that doesn't work?) they are terrible.  People who go on them will lose the weight, but almost all of them gain it back and then some.  While also doing other negative things to your body.  Not getting enough nutrients.  Or the right nutrients.  Stay away from low carb and low fat diets (of course, unless your Dr. tells you this).
Also, it would benefit us to balance omega 3's and 6's!  A lot of American's eat mostly 6's and virtually no 3's!

Anyways, I'd like to share some numbers of mine.  I recently went to the Cleveland Clinic for a physical, hadn't had 1 in yrs.  (Bad!  You should go once a year!)  My total cholesterol is 138 (should be under 200).  My HDL cholesterol is 60, for women, should be above 55.  My LDL (bad cholesterol) is 68.  Should be under 130.  My triglyceride value is 48, should be under 200.  My blood pressure was 100/62 (should be 120/80, or, even more optimal, which the medical field is trying to push to be 110/70, but that won't work with the insurance companies, at least that's what I learned through a class)  And resting heart rate is 44bpm.  Current weight=147lbs.  at 5'5".  Which means I have a 24.5 BMI, meaning if I gain 3lbs, I'll soon be classifed as overweight, according to our stupid government tables.  I was between 150-155 this summer with training, it was crazy!  lol :)  But what I'm getting at here, is the focus should be on eating healthy and being active (and you DON'T have to be as active as me, only moderately active!  My sis, who exercises for maybe 30-60min 4-5x a week had similar values :)  Even though I have been "overweight" this summer, and close to it now from those BMI tables, means nothing.  Look at the true evidence.  Oh, and 20% body fat-very good for my age and gender.  My obsession/passion is health and fitness, not trying to fit into a virtually unrealistic ideal that society has molded.  I have big hips, yay!  They help me do what I want to do-have great endurance while enjoying the outdoors.

A teacher of mine just sent me an email about a summer internship (pretty decent pay, yeah!!)  for a behavior coach opportunity at weight loss camps across the U.S. for kids/teenagers who are overweight/obese.  I was reading about it, and the focus is on mentoring, teaching about healthy eating, and physical activity.  If I do happen to get this awesome internship, I would be so greatful because then I can truly pursue my dream of helping others through health and fitness to enjoy life :)  (Although I am still unsure of my future job, this will help because it's in my field!!)

Growing Up

Well, I can say I am in a much better place than I was 1 year ago when I thought my world was crumbling apart.  When PT school did not work out for me, and when I was crying once, if not 2-3 times a week because I was failing and not enjoying it.  Thought I was failing in life.  Sometimes I wonder if I brought that upon myself, thinking I had to be studying every second of the day.  (Which...we almost did!  It was legit hard!)

The exercise science/kinesiology major is definitely for me.  I got 100% on my physiology of aging final, and 97.5 on my exercise physiology final.  Clearly, I'm in the right place.  :)  I think I'll have a 4.0 this semester, or close to it (haha-not sure about research methods-that's more of a challenge for me, but hoping for an A!)  This is also the 1st semester I haven't cried over a tough class.  I even cried every semester in undergrad-because I had to take some harder classes to get into PT school like chem and physics-challenging for me! 

I'm in such a great mood today, thought I'd write a blog about it.  I taught my first whole spin class this morning, and it went real well.  The other trainer said I did a great job, and some of the members came up to me after and said they really enjoyed the class!  I also get compliments on when I sub for a strength training class :)  I definitely feel like I was meant to teach fitness classes.  I just need to get a GroupEx certification so I can have my own class in a few sessions I'm hoping!  I work at the Y, have my personal training certification as well as a Spin cert.  I'm allowed to sub for other group ex classes because of those certifications.  Anyways..I think one of the reasons I am pretty good at teaching them is because I learned a lot from fitness DVDs I used to follow like Denise Austin, and various others, as well as taking classes myself.  I mean...every day in the summers or on break I would throw in a tape and workout!  I was thinking..maybe I could make my own DVD 1 day, but I don't even know how to go about that, I'd need help.

So, I am still unsure of where I want to go with this degree, but I have options :)  Either in a more clinical setting (cardiac or pulmonary rehab), or corporate fitness (I like fitness the most...but then, I also enjoy older adults and working with them too in a clinical setting...I'm very thorough, which I think would be good in the hospital).  I could maybe take 1 class a semester toward the PhD+work.  Ahhh I don't know.

Ideally, though, this is my dream job that I made up:  Owning a fitness center within a ski resort out West.  I don't even know if they have those.  But I should start one.  Then, I could own the fitness center, personal train, teach classes, and teach snowboard lessons.  Haha :)

Oh, and I have an AWESOME boyfriend who is an avid cyclist, and doesn't mind the amount I work out, because he often spends 14 hrs a week on his bike in season.  Nice.  I support that.

My sister has been working out more too.  Also wrote my mom an interval workout for her bike this winter-she gets bored riding the same moderate level all the time.  She enjoyed it-even sweated more wooo!  I wish I was closer to home sometimes so I could train her!  Us Perchinske's work hard!  Seriously, though, it's my mom's "always working at the best of your ability, no slacking" attitude, and my dad's super strong work ethic that has produced the same results in my sister and I :)  We have AWESOME parents!  Now...if only I could be promised a great job in the future where I can make an impact in people's lives, and Kristen a good job for next semester, she's graduating next week woo hoo!

Ok, I better get started on some schoolwork today, haha, I haven't yet! 

"Those who think they have not time for bodily exercise will sooner or later have to find time for illness."  Edward Stanley

"God is with those who persevere."

"Although the world is full of suffering, it is full also of the overcoming of it."  Helen Keller

Exercise Slows the Aging Process!

So, my teacher sent me some articles she found on cognitive function and aging.  For those of you who read this and don't know, I'm doing my thesis on it.  (Yes, for sure, I know I get excited about other things, but the mind is extremely fascinating to me, and so are studying the effects of aerobic exercise on the body, including the brain.)

Well, this article is titled, "Long-term treadmill exercise induces neuroprotective molecular changes in rat brain"
Rodents are similar to humans in the physiological workings of the body.  Anyways, they compared 3 groups-moderately exercised rats, handled but nonexercising group (handled on the treadmill somehow I guess), and a sedentary group.  What they found: That exercise...
-improved many brain parameters especially in the hippocampus.
-upregulated sirtuin-1, a protein in the brain that extends life
-stimulated mitochondrial biogenesis
- activated AMPK
-preventions of signs of neurodegeneration
"These findings are consistent with other reports showing that physical exercise has positive effects on hormesis."

I wasn't quite sure what mitochondrial biogensis was, so I looked it up, and came across this from another study.
"Moderate exercise also mimics CR by inducing mitochondrial biogenesis. Negative regulators of PGC-1alpha such as RIP140 and 160MBP suppress mitochondrial biogenesis. Another mechanism involved in mitochondrial maintenance is mitochondrial fission/fusion and this process also involves an increasing number of regulatory proteins. Dysfunction of either biogenesis or fission/fusion of mitochondria is associated with diseases of the neuromuscular system and aging, and a greater understanding of the regulation of these processes should help us to ultimately control the aging process." CR is caloric restriction.  I've read some studies for class saying that in rodents as well as 1 study involving humans for a short period of time, calorie restriction also helps slow the aging process and diseases associated with aging.  However, not many people are going to want to restrict their calorie intake so much for the rest of their lives :) So it's good news that exercise, and just a moderate amount, can slow the aging process.

This, I've kind of always known, and been scared of chronic illnesses later in life.  Yes, I worry about these things now, even though I'm young lol.  My grandmother had a heart attack, and my grandpa had a # of them, with triple by-pass surgery.  My other grandma has Alzheimer's.  I am going to try to do everything I can to avoid these diseases.  This is why I do what I do.  I want to see if I can live a very long, diseased free life.  This is why during my 40hr internship I decided to train for a full marathon at the age of 22.  This is why in grad school, I still work out just as intensely as the summer months.  This is why I sometimes workout twice a day in grad school.  Sometimes I lose sleep (only sometimes, don't worry) in order to get workouts done (still producing great school work!).  I am fully confident that when I have a full time job I'm still going to be able to work out for at least an hour a day.  I did it once and can do it the rest of my life, and I'm doing it now because school+assistantship is like a full time job.  Oh and if I decide to have children someday-I'll be that crazy jogging with a stroller or attaching the baby thing on the back of my bike.  Nothing will slow me down unless I get injured or die from the crazy adventures I tend to take on!  :)  Plus, if I didn't workout this much...I wouldn't be as fit to do the things I really love doing...like snowboarding for 8hrs a day or going surfing or backpacking through mountains...:)  Live the life you love!  Who cares what everyone else thinks.

Of course...you don't have to work out as intensely as I like to...this study..and a number of others show that it's just moderate exercise that is needed :)  (Although I think more intense exercise few days a week can produce even greater benefits....:)

I am also proud to say that I have no gray hairs at 24, almost 25, and my mom had her first at 18 LOL :)  Of course, she's wasn't as athletic like me :)   But I sure do look like her!  She looks pretty well for her age of 55-she still walks or rides her bike regularly.

http://www.ncbi.nlm.nih.gov/pubmed/18662766 (mitochondrial biogenesis article)

and

http://jap.physiology.org/content/111/5/1380.abstract (the exercise and brain health article)

It's so cool that sirtuin-1 extends life!  And that exercise can boost this protein!!