Nutrition During Intense Training

Maintaining proper nutrition intake during heavy blocks of training with multiple sessions per day or during multi-day races can be quite a challenge for most athletes.  There are several areas of concern that need to be addressed to ensure that adequate energy stores are available for high output racing or training, as well as for recovering from those sessions to be prepared for the next day’s training session or race.  Critical factors to consider include: total energy intake and macronutrient balance, hydration maintenance, and optimizing the timing of pre and post session nutrition needs.  The following article will review some of these concerns so a proper diet can be established.  For your benefit we also include a three day diet recall from 2012 Triathlete of the Year, Cameron Dye and Olympian and National Champion cyclist Evelyn Stevens.

Cameron Dye-three day food consumption

Evelyn Stevens-three day food consumption

Energy Balance

            The amount of energy that is expended during heavy training and racing can be extremely high, and failing to keep a close balance between energy expenditure and energy intake can lead to poor performance and even signs and symptoms of overtraining.  For cyclists who use a power meter, it is fairly easy to get a handle on the total amount of energy expended during training or racing on the bike by looking at the kilojoules (Kj) that are expended in each training session or race.  Even though in actual conversion there are 4.18 Kj per Calorie, the human body is only 20-25% efficient in terms of converting the chemical/food energy into actual power output at the pedal.  Therefore, if your power meter says that you burned 1800Kj of energy during a training session or race, you would have burned about 1800 Calories of food energy.  There is a relationship between the intensity of effort and the ratio of carbohydrate and fat that is burned that can be measured in a well equipped exercise physiology lab by a process known as indirect calorimetry.  In the absence of that kind of equipment and testing, it is reasonably accurate to consider that most well-trained athletes will burn about a 50/50% mix of carbohydrate and fat at low to moderate intensity training (aerobic endurance training).  As you work harder, the percentage of carbohydrate that is utilized will increase to nearly 80% or higher as you approach your lactate threshold (pace/power/speed that can be maintained for 1 hour, going all out).    The graph below shows the progression of heart rate, blood lactate, and then carbohydrate and fat use (displayed as calories per hour) for a well-trained runner during a progressive exercise test known as the FUEL test conducted at Boulder Center for Sports Medicine.  You can see that at low intensities, that this athlete actually utilizes even more fat than carbohydrate, but that as he reaches his threshold that the carbohydrate use skyrockets and fat use plummets.  Knowing this information can be very helpful when preparing for ultra-distance competitions where energy balance becomes a critical factor for success.

Keep in mind that once you have determined your exercise-related energy needs, you also need to consider your resting metabolic rate, which is typically about 10 X your body weight in pounds as a number of Calories per day.  For multisport athletes and non-cyclists, calculating actual energy use during exercise is more difficult since true power meters do not exist for most other activities than cycling, but it can be estimated using a resource like: http://www.hss.edu/womens-sports-health-fitness-calc.asp  In addition, about 10% of all the energy that you eat is burned in converting it into usable energy – which is known as the Thermic Effect of Food (TEF).  There is also a good calculator available here http://www.health-calc.com/diet/energy-expenditure-advanced  that will allow you to estimate total daily energy needs.  A 165 lb man riding 2 hours at fairly high intensity could require about 3500 Calories for the entire day.  This energy need is significant, but manageable with a relatively normal diet.

Once you consider more extreme training & racing, where daily energy needs can exceed 5,000 Calories a day then things get interesting.  Trying to eat a balanced athletic diet with a macronutrient breakdown of 40-50% carbohydrate, and between 20-30% each of fat and protein might not be realistic.  Knowing that the upper limit needs for protein are at approximately 1 gram per pound of body weight, for our 165-lb man we would have about 660 Calories coming from protein to meet protein needs…which would be only about 13% of a 5,000 Calorie daily intake.  You can read more about protein here:http://firstendurance.com/2013/02/11/protein-the-facts-you-need-to-know/ On these high energy intake days, we often see a shift to a higher percentage of fat intake, ideally with the healthier unsaturated fats like those found in nuts and nut butters, avocadoes, olive oil, etc.  Carbohydrate needs are significant and can’t be overlooked, but during these intense training and racing days the amount of carbohydrate taken in during exercise can be significant.  It would be fairly normal for an athlete to use an entire flask of EFS gel (100 grams carbohydrate) as well as a 20-ounce bottle of EFS drink mix (1 & 2/3 scoops, approx. 40 grams carbohydrate) during an intense 2 hour bike race.  The total carbohydrates from just those two fuel sources contains 140 grams, or 560 calories worth of carbohydrates.  There is a great article on fueling during exercise here:http://firstendurance.com/2013/01/11/how-to-fuel-during-endurance-events/ The pre-event/training session meal eaten 2-3 hours prior to the workout or race should also be predominantly carbohydrate based and might often contain another 600-800 calories of carbohydrate.  This meal should contain relatively low amounts of fats and protein, as digesting those both takes significantly longer than carbohydrates.  A post session or race recovery drink is also a very good idea to help replete glycogen stores rapidly, and should be consumed within 30-minutes of the end of exercise.  A serving of Ultragen contains an ideal balance of 60 grams (240 Calories) of carbohydrate and 20 grams (80 Calories) of protein.

Adding the pre-event meal, carbohydrate intake during the 2-hour race, and a serving of Ultragen for recovery, our 165-lb man would have taken in approximately 1400-1600 calories of carbohydrate, which does not include any additional snacks or meals beyond the pre-event meal.  For this example, eating a balanced dinner as well as possibly a snack or two will easily get him to his goal intake of 3,500 Calories for the day.  If this athlete was instead needing more than 5,000 Calories then looking for some extra high nutrient dense foods is going to be likely.  I have watched professional cyclists during a Grand Tour go to the food buffet and eat 3 full plates of food that would be considered a normal 800 calorie meal in each trip.  Eating 2400 Calories all at once in most settings might not be advisable, but during a major race you sometimes just need to eat when you can.  Eating a small snack just before bed, and also keeping a small snack right next to your bed can help keep you from waking up with extreme hunger during heavy phases of training or racing.

Hydration

            Fluid and electrolyte needs during intense training and racing are quite variable from person to person, and will also be high variable based on the environmental conditions, as well as your conditioning relative to the environment.  Figuring out your fluid needs during exercise can be done relatively easily using pre/post body weight measurement.  For more specific information on fluid and electrolyte needs during exercise please see: http://firstendurance.com/2008/08/28/the-complete-electrolyte-story/  As a simple rule, drinking 1 liter of water per day in addition to your exercise fluid losses should help you maintain proper hydration.  Weighing yourself at the start of end of each training session as well as in the morning and at night can also give you some idea regarding your fluid balance.  Some ProTour cycling teams weigh their riders before and after each stage to determine the riders’ fluid needs to regain hydration balance.  As a rule of thumb in normal conditions, most athletes will need between 1 and 2 bottles of fluid per hour of moderate exercise.  Extreme conditions and individual variations can lead to these fluid needs doubling, though.  On the flip-side, there are also athletes with incredibly low sweat rates whose fluid intake needs are far below average.  Tracking your weight, urine frequency and even color (keeping in mind that many vitamins can cause changes in urine color irrespective of fluid balance) can be helpful tools for monitoring your hydration level.  Resting heart rate and exercise heart rate for a given power/pace might also give you an idea of your hydration level, as with dehydration the blood viscosity is increased and heart rate will be elevated.

Meal Timing

            The typical time for many athletes who compete is for a morning start, but there are many other times where training and even racing is done throughout the day.  In most cases, a pre-event meal should be consumed between 2-3 hours prior to the event.  As mentioned above, this meal should be primarily carbohydrate based with minimal protein and especially minimal fat content.  It is important to have some sort of food routine, especially for competition so that you know your stomach will react similarly each time you race.  Even though it is incredibly common in Asia, I have many people look at me funny when I eat rice for breakfast as my pre-event meal.  I typically also have a scrambled egg and a little bit of ham, olive oil, and a dash of Parmesan cheese added to my breakfast rice.  The other pre-event staple meal for me is steel cut oats with honey, almond butter, and rice milk.   Completing the pre-event meal in the 2-3 hour window before a competition is sometimes a challenge, especially for early-start events like Ironman, but it is still important.  Organization and preparing the meal before going to bed often makes for an easier and smoother morning routine.

Post-training and post-race meals should ideally be consumed within an hour of completing exercise.  Even if you are going to have a post-race meal within 1 hour of finishing a race or training session, I still encourage athletes to consume a recovery drink as soon as possible after the finish to take advantage of the window to get glucose back into the muscles as soon as possible.  For the post-event meal, I like to focus on quality carbohydrate sources like potatoes or rice, as well as quality protein and healthy anti-inflammatory foods with high micronutrient content like kale, blueberries, and beets.

How PreRace Works

PreRace is designed to help endurance athletes improve performance. This revolutionary pre-exercise supplement is formulated with a mental acuity component comprised of DiMethyl Amino Ethanol (DMAE), metabromine and catechin, which combine to deliver a clear mental focus prior to exercise. Citrulline Malate and L-Taurine improve cardiac output, stimulate the nitric oxide (NO) system and clear lactate. The proprietary formula works synergistically with quercetin (a powerful antioxidant that improves time to exhaustion in endurance athletes) and 200mg of caffeine. PreRace comes as a flavor-free powder which can be added to any pre-exercise or during exercise drink, like EFS.

Physiological Adaptations

1. Enhances oxygenation of muscles
2. Increases muscle stamina
3. Increases nutrient absorption by blood
4. Improves time to exhaustion
5. Increases maximal workload
6. Improves oxidative ATP

Biochemical Processes

1. Enables significantly enhanced production of nitric oxide
2. Improves cardiac output
3. Augments vasodilation
4. Improves mitochondrial respiration
5. Stimulates removal of metabolic toxins (lactic acid, ammonia)

Citrulline Malate (2:1 Bonded)

CM is a mixture of citrulline, an amino acid involved in the urea cycle, and malate, a tricarboxylic acid cycle intermediate. Circulating levels of citrulline is directly related to endogenous argininie synthesis, possibly to an even greater degree than supplementing with straight argininie. Citrulline malate has been shown to significantly increase aerobic capacity, ATP production and PhosphoCreatine recovery after training, therefore reducing lactate and providing substrate for the aerobic energy production pathway. Early studies have also shown an antiaesthenic (resistance to muscle fatigue) effect.

Studies indicate that CM is involved in three physiological roles: 1) stimulates nitric oxide; 2) removes toxins; and 3) reduces lactic acid and ammonia. Therefore, citrulline malate may be useful for all athletes in maintaining energy levels, improving recovery, enhancing exercise performance and fatigue resistance.

Stimulates Nitric Oxide

In the body, nitric oxide (NO) serves several roles, mainly involving small blood vessels. Nitric oxide is synthesized from L-arginine and oxygen by various nitric oxide synthase (NOS) enzymes. The compounds are converted to nitric oxide, which in turn dilates the coronary artery thereby increasing its blood supply. Nitric oxide also serves as a neurotransmitter between nerve cells. Unlike most other neurotransmitters that only transmit information from a presynaptic to a postsynaptic neuron, the small nitric oxide molecule can diffuse all over and can thereby act on several nearby neurons, even on those not connected by a synapse. Nitric oxide is an important non-adrenergic, non-cholinergic (NANC) neurotransmitter in various parts of the gastrointestinal tract. In the stomach, it increases the capacity to store food and fluids.

The fact that nitric oxide increases blood flow should make it of interest to endurance athletes, as increased blood flow will serve to deliver more nutrients to muscles, thus helping muscles become more resistant to stress. The stimulation of NO has also been found to increase glucose transport in skeletal muscle significantly (Balon et al., 1997). The fact that nitric oxide acts to reduce inflammation should also make it of interest to endurance athletes as it has the potential to reduce the pain associated with subjecting muscles to extreme stress.

Removes Toxins

Citrulline acts to remove endotoxins such as lactic acid build up and ammonia by acting as an intermediary in the urea cycle. These endotoxins impair overall exercise performance and are produced by the body in response to intense physical exercise, protein metabolism and catabolic states.

Citrulline supplementation rapidly speeds up the removal of lactic acid and ammonia (waste products) from working muscles, resulting in better performance from the working muscle tissue. Ultimately, athletes can train harder and recover faster with each and every workout (Goubel F et al., 1997).

Reduces Lactic Acid and Ammonia

Research has demonstrated that citrulline malate has a protective effect against increased blood acidity and protects against ammonia poisoning. This study showed CM significantly increased bicarbonate (an acid buffer that soaks up lactic acid molecules), which allows exercise at a higher level before the negative effects of acidity affect exercise performance (Callis et al., 1991). Further studies showed supplementation with citrulline malate increases the rate of ammonia clearance without affecting ammonia accumulation during bicycle exercise (Vanuxem et al., 1990). This is because citrulline is involved in the urea cycle and therefore plays a role in the detoxification of ammonia.
CM positively influences the lactic acid metabolism leading to improved endurance performance. Healthy male subjects participated in a cycle ergometer study designed to determine CM’s effect on a) aerobic-anaerobic threshold; b) blood lactate accumulation; and c) 30 minute post-exercise blood lactate recovery. Two maximal cycling tests were performed with one group ingesting CM and another group ingesting a placebo. Aerobic-Anaerobic threshold was significantly higher in the CM group and 27% of subjects were able to achieve a higher maximal workload on the second test. (Janeira MA, 2006).

The human study done by Benedahan et al., 2002, demonstrated the great potential of citrulline malate supplementation to enhance aerobic performance. The most important finding of their research was significantly more energy produced aerobically (34% increase). But they also found a significant reduction in the sensations of fatigue and that rate of recovery, as measured by the rate of phospho-creatine recovery, improved by 20%. The researchers concluded that the increased aerobic ATP production, together with a reduced proportion of anaerobic energy supply, may contribute to the lower levels of fatigue experienced by the subjects (Benedahan et al., 2002).

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Benedahan, D., Mattei, J. P., Ghattas, B., Confort-Gouny, S., Le Guern, M. E. and Cozzone, P. J. (2002) Citrulline/malate promotes aerobic energy production in human exercising muscle. British Journal of Sports Medicine. 36 (4), 282-289.
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Callis, A., Magnan de Bornier, B., Serrano, J. J., Bellet, H. and Saumade, R. (1991) Activity of citruline malate on acid-base balance and blood ammonia and amino acid levels. Study in the animal and in man. Arzneimittelforschung. 41 (6), 660-663.
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Vanuxem, D., Duflot, J. C., Prevot, H., et al., (1990) Influence of an anti-asthenia agent, citrulline malate, on serum lactate and ammonia kinetics during a maximum exercise test in sedentary subjects. Seminaire des Hopitaux de Paris. 66, 477-481.

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L-Taurine

Taurine in the pharmaceutical and lab setting is synthesized through a combination of cysteine, methionine and vitamin E. It is naturally produced in testicles of many mammals. The major pathway for taurine synthesis occurs in the liver via the cysteine sulfinic acid pathway, which then acts as a metabolic transmitter, has a detoxifying effect and strengthens cardiac contractility. Taurine is defined as a non-essential amino acid and is found in high concentrations in the white blood cells, skeletal muscles, central nervous system as well as the heart muscles. In adults, but not children, this nutrient can be manufactured from methionine in the body and from cysteine in the liver.

This sulfur-containing amino acid functions with glycine and gamma-aminobutyric acid as a neuroinhibitory transmitter. At times of extreme physical exertion, the body no longer produces the required amounts of taurine and a relative deficiency results – essentially, in long exhaustive exercise taurine concentrations are significantly reduced. These reductions in taurine concentration can lead to decreased physiological parameters and performance (Manabe et al. 2003).

Through its cardio and oxidative protective roles, oral administration of taurine can improve exercise performance significantly. Furthermore, pre-exercise taurine administration can reduce muscle damage caused by endurance training. Researchers also theorize that it is through the cellular protective properties that taurine attenuates exercise-induced DNA damage and enhances the capacity of exercise.

In a study performed by Zhange et al, 11 healthy-aged men participated in two separate cycle ergometer tests supplementing orally with taurine prior to exercise. The study results showed significant increases in VO2max, exercise time to exhaustion and maximal workload. Following exercise, the increase in taurine concentration correlated positively with exercise time to exhaustion and maximal workload (Zhang et al, 2004).

Endurance-trained subjects performed an exhaustive bout of endurance exercise at three different times. Subjects were placed into three groups: caffeine and taurine, caffeine with no taurine, and a placebo. In this double-blind placebo-controlled study, the subjects ingesting the caffeine and taurine drink showed improved cardiovascular stroke volume (Baum M Weiss M, 2001). The authors of this study claim this was due to a reduced endystolic diameter and volume.

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Baum M, Weiss M. The influence of a taurine containing drink on cardiac parameters before and after exercise measured by echocardiography. Amino Acids. 2001; 20(1):75-82.

Manabe et al. Decreased blood levels of lactic acid and urinary excretion of 3-methylhistidine after exercise by chronic taurine treatment in rats. Journal of Nutr Sci Vitaminol (Tokyo) 2003: 49(6):375-80.

Yatabe Y, et. al. Effects of taurine administration in rat skeletal muscles on exercise. J of Orthopedic Science. 2003: 8(3):415-9.

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Matsuzaki Y et. al. Decreased taurine concentration in skeletal muscles after exercise for various durations. Medicine Science Sports Exercise. 2002; 34(5):793-7.

Malic Acid

Malic acid is the only metabolite of the Krebs Cycle which falls in concentration during exhaustive physical activity. Malic acid is involved in the production of energy in the body under both aerobic and anaerobic conditions. During anaerobic conditions, malic acid has an ability to remove the accumulation of reducing equivalents. Human studies have shown that after endurance training, athletes’ muscles were characterized by a 50% increase in the malate-aspartate redox shuttle enzymes. In both animals and humans, when there is an increased demand for ATP there is an additional demand and utilization of malic acid. Malic acid stimulates oxygen consumption by increasing mitochondrial uptake of other substrates. It also stimulates the removal of components that build up under hypoxic conditions and inhibit ATP production (Wu J et al 2006).

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Wu J et al. Effects of L-Malate on physical stamina and activities of enzymes related to the malate-aspartate shuttle in liver of mice. Physiology Res. 2006 Mar 23.

Neuro-Stimulant: Metabromine-Caffeine-Catechin-DMAE

This proprietary combination is designed to enhance performance through a neurological stimulus improving clarity, focus and concentration. The combination of theobromine, caffeine, and catechin (from green tea and DMAE) works synergistically to elevate mood and enhance performance.

Metabromine

Metabromine, derived from the seed of the cacao tree (Theobroma cacao), contains procyanidins, theobromine and caffeine – which are natural methylxanthines. Metabromine’s mechanism of action results from the combination of caffeine, theobromine and procyanidins. The standardized levels of theobromine and caffeine produce a mild stimulating effect without over-stimulation of the central nervous system. Theobromine is the primary alkaloid found in cocoa and chocolate, and is one of the causes of chocolate’s mood-elevating effects. Research indicates a possible interaction of the methylxanthines with the procyanidins which promote a sustained energizing effect.

Theobromine is well documented as a vasodilator as well as having mild stimulant effects (Mumford, 1994). It is extremely well tolerated in humans at doses as high as 0.8 to 1.5 g of the pure compound (IARC monographs). Theobromine has very different effects than caffeine on the human body; it is a mild, lasting stimulant with a mood improving effect, whereas caffeine has a strong, immediate effect and increases awareness. Simultaneous increases in lipid and carbohydrate oxidation is believed to mediate the caffeine-induced stimulation of energy expenditure (Bracco, et al, 1995). Research has also shown that caffeine decreases the reliance of glycogen during exercise and increases endurance, possibly by a direct effect on adipose tissue and active muscle.

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Jan; 49 (1): 101-7.

Bracco D, et al., Effects of caffeine on energy metabolism, heart rate and methyl xanthine metabolism
in lean and obese women. Am. J. Physiol 1995 Oct; 269: E671-8

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Clin Pharmacol. 1996; 51 (3-4): 319-25.

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Comm. 272, 236-241 (2000).

Yoshida T, Sakane N, Umekawa T, Kondo M. Relationship between basil metabolic rate, thermogenic response to caffeine and body weight loss following combined low calorie and exercise treatment in obese women. Int J Obes Relat Metab Disord 1994 May; 18(5): 345-50.

Caffeine

Caffeine stimulates the central nervous system (CNS), increases the release of adrenaline, increases the use of body fat as fuel and spares glycogen. Adrenaline release is accomplished through caffeine’s effect on epinephrine and nor-epinephrine. Many athletes seek this CNS excitatory response to increase alertness and to give them the extra ‘energy’ needed for their workouts. More importantly, caffeine mobilizes free fatty acids (FFA) in the blood. Increased FFA in the blood allows the body to use fat as a fuel source. The use of fat as fuel allows the body to spare glycogen (carbohydrates) for later use in exercise.

Kovacs et al. (1998) studied well-trained cyclists. The results of this study support the use of caffeine during competition to improve performance. In this study, 15 cyclists ingested different levels of caffeine in addition to a carbohydrate-electrolyte drink during a time trial. The highest caffeine doses (225 and 320 mg) resulted in a 5% increase in power relative to control trials without caffeine (308 + 9 W and 309 + 10W versus 295 + 9W, respectively). The amount of caffeine ingested during this study was relatively small, and yielded caffeine concentrations in the urine of less than 5 mg/L for the participants.

Another recent study by Cox et al. (2002) supported the use of caffeine both before and during cycling performance. This study involved a cycling time trial which occurred after 2 hours of steady state cycling at 70% of VO2max. Several different patterns of caffeine ingestion were utilized, including different levels before and during the trial. None of the methods caused an increase in caffeine concentration in the urine to exceed 12ug/ml. These results also demonstrate that ingestion of 1-3 mg/kg of caffeine produced the same level of performance enhancement (~3%) as did the higher levels of caffeine intake (6 mg/kg).

Yeo et al. (2005) published a recent study that looked at the effects of caffeine ingestion on carbohydrate oxidation. Eight male cyclists exercised for 120 minutes on three separate occasions. During exercise, cyclists ingested either a 5.8% glucose solution (Glu; 48 g/h), 5.8% glucose solution with caffeine (Glu+Caf, 48 g/h + 5 mg·kg·h-1), or plain water (Wat). Average exogenous CHO oxidation over the 90- to 120-min period was 26% higher (p < 0.05) in Glu+Caf (0.72 +/- 0.04 g/min) compared with Glu (0.57 +/- 0.04 g/min). Total CHO oxidation rates were higher (p < 0.05) in the CHO ingestion trials compared with Wat, but they were highest when Glu+Caf was ingested (1.21 +/- 0.37, 1.84 +/- 0.14, and 2.47 +/- 0.23 g/min for Wat, Glu, and Glu+Caf, respectively; p < 0.05). There was also a trend (P = 0.082) toward an increased endogenous CHO oxidation with Glu+Caf (1.81 +/- 0.22 g/min vs. 1.27 +/- 0.13 g/min for Glu and 1.12 +/- 0.37 g/min for Wat). In conclusion, compared with glucose alone, 5 mg/kg caffeine (approximately 350mg caffeine for a 150lb athlete) co-ingested with glucose increases exogenous CHO oxidation, possibly as a result of an enhanced intestinal absorption.

Doherty et al, (2005) recent meta-analysis of the use of caffeine ingestion on rate of perceived exertion (RPE) supports the use of caffeine as an ergogenic aid. Twenty-one studies were reviewed. In comparison to placebo, caffeine reduced RPE during exercise by 5.6% (95% CI). These values were significantly greater (p<0.05) than RPE obtained at the end of exercise (RPE % change, 0.01%; 95%). In addition, caffeine improved exercise performance by 11.2% (95% CI; 4.617.8%). Regression analysis revealed that RPE obtained during exercise could account for 29% of the variance in the improvement in exercise performance. These results demonstrate that caffeine reduces RPE during exercise, which may partly explain the subsequent ergogenic effects of caffeine on performance.

In a 2004 study, Doherty et al. investigated the effects of caffeine ingestion on a ‘preloaded’ protocol that involved cycling for 2 min at a constant rate of 100% maximal power output immediately followed by a 1-min ‘all-out’ effort. Eleven male cyclists completed a ramp test to measure maximal power output. On two other occasions, the participants ingested caffeine (5 mg·kg) or placebo. Ratings of perceived exertion (RPE; 6-20 Borg scale) were lower in the caffeine trial by approximately 1 RPE point at 30, 60 and 120 s during the constant rate phase of the preloaded test (p <0.05). The mean power output during the all-out effort was increased following caffeine ingestion compared with placebo (794+/-164 vs. 750+/-163 W; p=0.05). Blood lactate concentration 4, 5 and 6 min after exercise was also significantly higher by approximately 1 mmol. in the caffeine trial (p <0.05). These results suggest that high-intensity cycling performance can be increased following moderate caffeine ingestion and that this improvement may be related to a reduction in RPE and an elevation in blood lactate concentration.

McClellan and Bell (2004) looked at the ergogenic role of ingesting coffee (COF) prior to the subsequent ingestion of anhydrous caffeine (CAF). Thirteen subjects performed 6 rides to exhaustion at 80 % VO2max 1.5 h after ingesting combinations of COF, decaffeinated coffee (DECOF), CAF, or placebo. Time to exhaustion was significantly greater for all trials with CAF compared to placebo. In conclusion, the prior consumption of COF did not alter the ergogenic effect of the subsequent ingestion of anhydrous CAF.

Brinbaum et al. (2004) observed the physiological effects of caffeine on cross-country runners during submaximal exercise. Ten college-age subjects (5 women; 5 men) volunteered to participate in this study. After completing a VO2max test, each subject completed 2 30-minute runs at 70% VO2max on the treadmill, 1 after ingesting caffeine and the other after ingesting a placebo. Tidal volume (TV), alveolar ventilation (VA), and rating of perceived exertion (RPE) were significantly different (p < 0.05) between treatment and control groups. The results suggest that the ingestion of caffeine at 7 mg·kg of body weight prior to submaximal running might provide a modest ergogenic effect via improved respiratory efficiency and psychological lift.

References:
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Cox GR, Desbrow B, Montgomery PG, Anderson ME, Bruce CR, Macrides TA, Martin DT, Moquin A, Roberts A, Hawley JA, Burke LM. Effect of different protocols of caffeine intake on metabolism and endurance performance. J Appl Physiol. 2002; 93(3):990-9.

Doherty, P. M. Effects of caffeine ingestion on rating of perceived exertion during and after exercise: a meta-analysis. Scandinavian Journal of Medicine & Science in Sports. 2005; 15, 69.

Doherty M, Smith P, Hughes M, Davison R. Caffeine lowers perceptual response and increases power output during high-intensity cycling. J Sports Sci. 2004 Jul;22(7):637-43. Department of Sport, Exercise and Biomedical Sciences, University of Luton, Luton LU1 3JU.

Essig D, Costill DL, Van Handel RJ. Effects of caffeine ingestion on utilization of muscle glygogen and lipid during leg ergometer cycling. International Journal of Sports Med. 1980; 1:86-9.

Fisher SM, McMurray RG, Berry M, et al. Influence of caffeine on exercise performance in habitual caffeine users. International Journal of Sports Med 1986;7:276-280.

Greer F, Friars D, Graham TE; Comparison of caffeine and theophylline ingestion: exercise metabolism and endurance.J Appl Physiol 2000 Nov;89(5):1837-44 Department of Human Biology and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada N1G 2W1.

Ivy JL, Costill DL, Fink WJ, et al. Influence of caffeine and carbohydrate feedings on endurance performance Med Science Sports and Exercise. 1979; 11;6-1.

Kovacs EMR, Stegen JHCH, Brouns F. Effect of caffeinated drinks on substrate metabolism, caffeine excretion, and performance. J Appl Physiol 1998; 85: 709-715.

McLellan TM, Bell DG. The impact of prior coffee consumption on the subsequent ergogenic effect of anhydrous caffeine. Int J Sport Nutr Exerc Metab. 2004 Dec;14(6):698-708.

Yeo SE, Jentjens RL, Wallis GA, Jeukendrup AE. Caffeine increases exogenous carbohydrate oxidation during exercise. J Appl Physiol. 2005 Sep;99(3):844-50. Epub 2005 Apr 14.

World Anti-Doping Association http://www.wada-ama.org

Caffeine Drug Info: http://www.nlm.nih.gov/medlineplus/druginfo/uspdi/202105.html

Catechin

Green tea is made up of polyphenols (catechins) and flavonols. The primary catechins found in green tea with the most potent antioxidant activity are epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG). EGCG makes up 10 – 50% of the total catechin content and appears to be the most powerful of the catechins. Green tea’s antioxidant activity is 25 – 100 times more potent than vitamins C and E. Green tea is generally standardized to total polyphenol content and/or EGCG content. For years this extract has been widely studied for its wealth of health benefits including blood clotting reduction, cholesterol lowering, weight loss and as an anti-carcinogen. Recently green tea has also shown an ability to improve endurance performance.

A study done on mice investigated the effects of green tea extract (GTE), on endurance capacity, energy, metabolism, and fat oxidation in mice over a 10-week period. Swimming times to exhaustion for mice fed 0.2-0.5% (wt/wt) GTE were prolonged by 8 – 24%. The effects were dose-dependent and accompanied by lower respiratory quotients and higher rates of fat oxidation as determined by indirect calorimetry. In addition, feeding with GTE increased the level of beta-oxidation activity in skeletal muscle. Plasma lactate concentrations in mice fed GTE were significantly decreased after exercise, concomitant with increases in free fatty acid concentrations in plasma, suggesting an increased lipid use as an energy source in GTE-fed mice. Epigallocatechin gallate (EGCG), a major component of tea catechins, also enhanced endurance capacity, suggesting that the endurance-improving effects of GTE were mediated, at least in part, by EGCG. The beta-oxidation activity and the level of fatty acid translocase/CD36 mRNA in the muscle was higher in GTE-fed mice compared with control mice. These results indicate that GTE is beneficial for improving endurance capacity and support the hypothesis that the stimulation of fatty acid use is a promising strategy for improving endurance capacity.

In a new Korean study, published on-line in the journal Life Sciences (doi: 10.1016/j.lfs.2005.11.001), the effect of EGCG on hypoxia-induced apoptosis for human haematoma cells was examined. This study found Epigallocatechin gallate (EGCG), the main extract from green tea, improves oxygen flow to tissues deprived of adequate supply.

Hypoxia occurs when oxygen supply to tissue or the whole body is restricted. If cells are denied oxygen for too long, they die – a process called apoptosis. The most well known form of hypoxia is altitude sickness, which can occur when travelers go above an altitude of 6,000 – 8,000 feet (1,829 to 2,438 meters). Cells were exposed to varying concentrations of the tea extract (12.5, 25, 50, 100 micromoles) and the number of live cells tested. In the control cell culture, 40 per cent of cells died due to lack of oxygen. In the test groups, although cell death was decreased for all EGCG concentrations, exposure to 12.5 micromoles of EGCG reduced cell death by 10%. All cells were still alive after exposure to 100 micromoles of EGCG. The mechanism was theorized to result from green tea preventing the expression of a certain enzyme called caspase 3, which plays an important role in programmed cell death.

References:
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Cooper R, Morre DJ, Morre DM.Medicinal benefits of green tea: part I. Review of noncancer health benefits.J Altern Complement Med. 2005 Jun;11(3):521-8.

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Liao S, Kao YH, Hiipakka RA.;Green tea: biochemical and biological basis for health benefits.
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Murase T; Haramizu S; Shimotoyodome A; Nagasawa A; Tokimitsu., Green tea extract improves endurance capacity and increases muscle lipid oxidation in mice. Am J Physiol Regul Integr Comp Physiol 2005 Mar; 288(3):R708-5 I Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi 321-3497, Japan.

DMAE

Dimethylaminoethanol (DMAE), related to choline and a biochemical precursor to the neurotransmitter acetylcholine, is found naturally in fishes like sardines and anchovies. It is reported to have nootropic effects. DMAE, also known as dimethylethanolamine or Dimethylaminoethanol, can be interpreted to induce a psychophysiological state of better feeling or well-being on both levels of analysis – mood and electrical pattern of brain activity.

It is believed that dimethylaminoethanol is methylated to produce choline in the brain. It is known that dimethylaminoethanol is processed by the liver into choline; however, the choline molecule is charged and cannot pass the blood-brain barrier. Short term studies show an increase in vigilance and alertness, with a positive influence on mood. (Pfeiffer, 1957)

Pfeiffer C, et al. Stimulant effect of 2-dimethylaminoethanol; possible precursor of brain acetylcholine. Science 126(3274):610-611, 1957. [1]

Dimpfel W, Wedekind W, Keplinger I. Efficacy of dimethylaminoethanol (DMAE) containing vitamin-mineral drug combination on EEG patterns in the presence of different emotional states. European Journal Medical Research 8(5):183-191, 2003. [2]

Zahniser NR, Chou D, Hanin I. Is 2-dimethylaminoethanol (deanol) indeed a precursor of brain acetylcholine? A gas chromatographic evaluation. Journal of Pharmacology and Experimental Therapeutics 200(3):545–559, 1977

Quercetin

Quercetin is a flavonoid and, more specifically, a flavonol. It is the aglycone form of a number of other flavonoid glycosides, such as rutin and quercitrin found in citrus fruit. Quercetin is found to be the most active of the flavonoids in studies, and many medicinal plants owe much of their activity to their high quercetin content. Quercetin works to potentiate the effects of both caffeine and nitric oxide.

This flavonol has demonstrated significant anti-inflammatory activity because of direct inhibition of several initial processes of inflammation. For example, it inhibits both the manufacture and release of histamine and other allergic/inflammatory mediators. In addition, it exerts potent antioxidant activity and vitamin C-sparing action. In vitro and animal studies suggest that quercetin inhibits tyrosine kinase and nitric oxide synthase and that it modulates the activity of the inflammatory mediator, NF-kappaB.

More importantly to endurance athletes, Quercetin acts to potentate the effects of caffeine. Quercetin is reported to help control cyclo-oxygenase activity. Cyclo-oxygenase activity increases in the body during periods of high physical stress (Garcia-Mediavilla V et al.). Studies indicate this powerful flavanoid works synergistically with theobromine and caffeine to further extend the CNS stimulant effects.

References:
MacRae HS, Mefferd KM. Dietary antioxidant supplementation combined with quercetin improves cycling time trial performance. Int J Sports Nutrition and Exercise Metabolism. 2006 Aug:16(4): 405-19.

Conquer JA, Maiani G, Azzini E, et al. Supplementation with quercetin markedly increases plasma quercetin concentration without effect on selected risk factors for heart disease in healthy subjects. J Nutr. 1998; 128:593-597.

Hollman PCH, van Trijp JMP, Mengelers MJB, et al. Bioavailability of the dietary antioxidant flavonol quercetin in man. Cancer Lett. 1997; 114:139-140

Hollman PCH, Gaag MVD, Mengelers MJB, et al. Absorpotion and disposition kinetics of the dietary antioxidant quercetin in man. Free Red Biol Med. 1996; 21:703-707.

Garcia-Mediavilla V et al,. The anti-inflammatory flavones quercetin and kaempferol cause inhibition of inducible nitric oxide synthase, cyclooxygenase-2 and reactive C-protein, and down-regulation of the nuclear factor kappaB pathway in Chang Liver cells.
Eur J Pharmacol. 2007 Feb 28;557(2-3):221-9. Epub 2006 Nov 15.