Supplement Savvy: More Questions, MOHR Answers - 6-14-04!

In this article I cover studies about the effects of caffeine and the importance of post-exercise nutrition.

Caffeine Studies

The Effect Of Caffeine On Military Tasks During A Night Of Sleep Loss
MSSE Abstract #0140

Soldiers and many others out there aren't punching the clock at a 9-5 job. Therefore, fatigue is common, which could negatively effect your workouts. The purpose of this study was to determine the effects of caffeine on a 2-hour forced march and sandbag piling task after a morning of a night of sleep deprivation.

Subjects were given either 400 mg of caffeine or a placebo and then asked to complete the previously mentioned tasks to determine the physiological and perceptual strain with and without caffeine.

It was concluded that the caffeine was effective in improving performance during the early phase of a self-paced sandbag piling task. Since that's probably not the most common exercise most of us regularly perform, the results must be extrapolated to what we do.

Therefore, it can be inferred that caffeine may help performance in the gym too.

SciFit Caffeine
Studies have shown Caffeine to have significant effects on physiological response and performance of trained athletes.
[ Click here to learn more. ]

Influence Of Caffeine Ingestion On Fluid-Electrolyte, Psychological And Physiological Responses During An Exercise Heat-Tolerance Test
MSSE Abstract #0142

Speaking of caffeine, it is often recommended that athletes refrain from caffeine consumption because it may have a diuretic effect, thereby causing a fluid-electrolyte imbalance and exaggerating physiological strain.

Therefore, the purpose of this study was to measure just that; does the consumption of a controlled dose of caffeine, in chronic caffeine users, effect fluid balance and hydration status?

Well, the researchers gave subjects either 0, 3, or 6 g/kg/day of caffeine and asked subjects to perform a specific prescribed exercise routine. It was determined that acute caffeine ingestion, in chronically consuming subjects, did not alter heat-tolerance or hydration status.

Moral of the story: if you regularly drink caffeine, it won't have a negative effect on hydration status (i.e., won't help dehydrate you).

This is important because no matter how perfect you think your nutrition program is, if you aren't well-hydrated, you won't be able to perform your best.

Post-Exercise Nutrition

Low-carb mania has swept the nation; everything from pasta to milk to pizza is now promoted as low-carb. However, as athletes and bodybuilders, low-carb may not always be the best thing.

In fact, carbohydrates are a necessary form of energy for optimal performance.

What's also important is the type of carbohydrate consumed-glucose, fructose, sucrose, etc all have different effects on blood sugar and, subsequently, how they are absorbed an ultimately utilized to restore glycogen (the storage form of carbohydrate that's necessary for activity).

Effect Of Different Types Of Carbohydrate Supplementation On Glycogen Supercompensation In Rat Skeletal Muscle
MSSE Abstract #0154

This is one of very few studies comparing various forms of carbohydrate on glycogen restoration. Granted, this study was conducted in rats; however, females often recognize the male gender as rats, so this study may be very applicable.

Anyhow, in this study the rats used were trained using a swimming program (typically researchers tie small weights to the tails of rats to ensure they move to stay afloat-if they don't, they'll drown).

The rats swam 6 hours/day (glad I wasn't a subject) to ensure glycogen depletion. Then, rats were fed either 5% sucrose, 5% glucose, 5% fructose, or water. The rats were then killed (again, glad I wasn't a subject) and the glycogen content of their muscles was measured.

It turns out that the glucose supplementation resulted in a significant increase in glycogen synthesis when compared to the other forms of carbohydrate. So how should this be interpreted?

Well, after a grueling workout where glycogen is depleted to a great extent, supplementing with a glucose based product may in fact enhance the uptake of carbohydrates to allow you to better perform your next workout.

Endurox R4
Endurox R4 enables you to train harder and better the next day and everyday.

Dietary Whey Protein Modulates the Liver Glycogen Level and Glycoregulatory Enzymes Activity in Exercise Rats
MSSE # 0159

Again, glycogen is the storage form of carbohydrate and is a necessary fuel for working out. In fact, once glycogen is depleted, you'll have a hell of a time continuing at the intensity as when you first started working out.

Therefore, maintaining optimal glycogen is key. Contrary to the above study, however, this one use whey protein compared to casein and soy to determine the effects on glycogen restoration.

Rats were divided into 3 groups in which they were provided diets that provided either 20% whey protein, 20% soy protein, or 20% casein protein. After testing the rat muscles, it turned out that the rats fed whey protein had a significant increase in glycogen over the soy and casein protein.

Combining the two studies above, it looks like a post-workout drink combining both glucose and whey protein would be perfect to speed up the recovery process and better prepare you for the next workout.

Optimum 100% Whey Protein
100% Whey Protein is a potent pharmaceutical grade protein supplement. Each serving delivers 23 grams of high biologically valued protein and only one gram of fat.
[ Click here to learn more. ]

Postexercise Muscle Glycogen Recovery is Enhanced With a Carbohydrate-Protein Supplement
MSSE Abstract #0286

Here we have a study that did put the two results above together; so even though speculation is OK, it's even better to have an actual study to determine the true effects of something.

Here researchers sought out to determine if a liquid carbohydrate-protein drink enhanced recovery vs. an isoenergetic a liquid carbohydrate drink. Subjects were asked to cycle as intensely as possible to ensure glycogen depletion.

Subjects were then given a liquid carbohydrate-protein supplement (glucose and whey protein) vs. carbohydrate only. Muscle glycogen restoration was greater in the carb-protein group; however, this did not correlate to an increase in subsequent performance.

This study did not measure protein resynthesis, which is also an important component of recovery.

So let's recap what we learned from this year's ACSM meeting.

  1. Caffeine may boost performance when taken before a workout.
  2. If you are a chronic caffeine consumer, consuming caffeine will not negatively effect hydration status (but of course it's still recommended to drink adequate fluids)
  3. A liquid post-workout supplement comprised of glucose and whey protein will enhance recovery over carbohydrates alone.
  4. Three sets of resistance training is equal to one set in terms of strength increases; however, only one-set of training increased body fat losses during an eight-week period.