Lab Exercise #10: Part One- Does Exercise Affect the Glycemic Response to Monster Energy Drink?
INTRODUCTION:
As nurses or other health professionals you may have numerous opportunities to participate in clinical trials. This type of activity is a common practice at any regional health center. It provides its health professionals with an opportunity for professional development and allows them to pursue ideas that have peaked their curiosity. In this exercise we will conduct a clinical trial on energy drinks.Billions of cans of energy drink are ingested every year and we (Drs Ragsdale and Wilson: See References Below) have studied the response to Red Bull and Monster Energy drinks in non-exercised students. Oddly enough, nobody knows how exercise affects our glycemic response to an energy drink. This might be helpful in understanding what happens to our glycemic response in general and when there is access to “energy” after exercise when energy drinks are often consumed.
For this laboratory, you will either ride an exercise bike in the lab prior to consuming a Monster Energy Drink or there will be no prior exercise to consuming a Monster Energy Drink.
Part of learning how to conduct a clinical trial is also about learning how an institution regulates such activities. At WSU, as with other institutes of higher learning, a review board reviews all of the documents prior to investigation and approves the research as submitted. Below is a description of this process.
WHAT IS AN INSTITUTIONAL REVIEW BOARD (IRB) AND AN INFORMED CONSENT DOCUMENT (ICD)?
Any investigator that wishes to do studies on humans must first obtain approval from the Human Subject Institutional Review Board (IRB) at the institution where a study is being performed, as required by the U.S. Federal Government. The IRB is a University committee that looks at a proposed study and determines that it is safe and that no unreasonable activities will be required of the study volunteers. More information about the Winona State IRB can be obtained at this website: All Bio 212 and 323 students are required to examine the Human Subjects Training Module and D2L quiz as a general class requirements:
The IRB approves what is called an Informed Consent Document that must be obtained from each person volunteering for a procedure prior to their starting the study. An informed consent document helps to tell the participant exactly what sort of study they are choosing to volunteer for. It demands that the investigator (Drs. Ragsdale and Wilson) not perform anything that has not been described to the volunteer. It also describes the risks that could be associated with participation in a study. It isa way to ensure that both the volunteer and the investigator agree on what the study will examine and what the participant will be required to do. The study volunteer, the investigator and a witness must all sign this document.
A course can receive a “blanket” approval from the IRB for regular laboratory activities. This blanket IRB is what we use for the regular lab activities that you participate in AP 212 and Gen. Physiology Lab. This Energy Drink lab activity has been given a special IRB approval, so you can see what an informed consent document really is and how it is used. This documentation also allows Drs Ragsdale and Wilson to publish this data. You are doing real research.
The protocol is spelled out in the following pages. No one is forced to participate, but we hope that you will take the opportunity to participate in science. Additional details can be found on the informed consent document. Please download the Informed consent and read over the details. This is our documentation/contract for the volunteers.
BACKGROUND INFORMATION:
Glycemic response describes how blood glucose increases following carbohydrate ingestion (eating or drinking), resulting in insulin secretion from the pancreas. Secretion of insulin by the beta-cells of the pancreas is the key that permits the postprandial blood glucose elevation to return to normal. This happens when insulin binds to insulin receptors (receptors are locks that fit a key) on sensitive tissues such at skeletal myocytes, hepatocytes, and adipocytes. The insulin makes these tissues become glucose permeable so that glucose can leave the blood. Normal blood glucose is called euglycemia (70 to 140 mg/dL fasting), however elevated blood glucose is called hyperglycemia (>140 mg/dL fasting or >180 mg/dL after a meal or challenge) and low blood glucose is called hypoglycemia (<70 mg/dL).
Insulin sensitive tissues can be made glucose permeable when the key (insulin) opens the locks (insulin receptors). With regards to insulin secretion, do you have only a few keys or many keys to open the locks? Type-1 diabetes results from the inability to secrete any insulin and an inability to make these tissues permeable to glucose. If the key does not fit or if the internal lock mechanism does not work,insulin may still be unable to permit glucose to enter these tissues and the glucose accumulates in the blood resulting in insulin insensitivityand potentially type-2 diabetes.
The glycemic response of an individual to a glucose challenge is a function of many things. First, the amount of sugar ingesteddetermines how much glucose challenge is present (did the person drink pure maple syrup or reduced calorie maple syrup?). Second, the amount and time of insulin secreted is important in determining how quickly insulin appears in blood after the blood glucose begins to increase (was the person type 1 diabetic and unable to secrete any insulin?). Third, the glycemic response is a function of whether the keys (insulin) can open the locks that permit glucose to enter the insulin sensitive tissues. Fourth, the rate of glucose removal by insulin sensitive tissues is a function of how much blood is delivered to insulin sensitive tissues (increased perfusion means increased glucose removal). Exercise is a classic activity that often results in increased insulin sensitivity (independent of perfusion) and improved insulin sensitivity (insulin keys open locks more efficiently), in both type 2 diabetics and non-diabetics alike (Conn et al 2014). [Conn VS,Koopman RJ,Ruppar TM,Phillips LJ,Mehr DR,Hafdahl AR. Insulin Sensitivity Following Exercise Interventions: Systematic Review and Meta-Analysis of Outcomes Among Healthy Adults. J Prim Care Community Health.2014;5:211-22.]
What is in a drink and what effect will a drink have on our ability to maintain euglycemia? We know that if the drink contains a lot of glucose it represents a larger glucose challenge, but what about the other ingredients? Can the other ingredients change the physiology of your body and our glycemic response? Energy Drinks are popular with college students because they claim to provide consumers with “energy”. They contain caffeine and many other ingredients that could also alter muscle perfusion, insulin secretion, insulin sensitivity, and glycemic response.
What is this “energy” that Energy Drink marketing campaigns depend upon? Energy can mean metabolic ability to generate greater amounts of ATP, but energy can also be psychological (for example, hopefully nobody really believes that drinking Red Bull “gives you wings”). Ingested items that contain sugar can be metabolized to produce ATP used for muscle contraction and a myriad of other activities associated with exercise. Caffeine may be more psychological. This laboratory activity will attempt to determine if ingestion of Monster Energy Drink creates a glycemic response and whether exercise completed before ingestion changes our glycemic response. Monster energy drink was chosen for this lab activity only because of its availability in its caffeinated form and because of the high consumption rates.
People often ingest an energy drink “after” a work out, when physical activity changes our insulin sensitivity and glycemic response. Billions of cans of energy drink are ingested every year and we (Drs Ragsdale and Wilson: See References Below) have studied the response to Red Bull and Monster Energy drinks in non-exercised students. Oddly enough, nobody knows how exercise affects our glycemic response to an energy drink. This might be helpful in understanding what happens to our glycemic responseand access to “energy” after exercise when energy drinks are often consumed.
FR Ragsdale, Energy Drinks – the Elixirs of Our Time, In: T Wilson, NJ Temple, eds. “Beverages in Health and Nutrition 2nd Edition”. Springer/Humana Press Inc, Totowa, N.J. January 1, 2016.
Denzer DL, Ragsdale FR, Wilson T. Effects of Monster energy drink on cardiovascular and renal function in Young Adults. Int J Food Nutr Sci 2016: DOI: 10.15436/2377-0619.16.046
FR Ragsdale, TD Gronli, SN Batool, EC McMahon, KL Ryan, KD West, TW Nalli, CM, Mannello, CJ Sell, PJ McCann, GM Kastello, T Hooks, T Wilson. Effect of Red Bull Energy Drink on Cardiovascular and Renal Function. Amino Acids. 2010; 38:1193-2000.
Monster Energy DrinkServing Size: 240 ml Calories:101 Caffeine86 mg
% Daily Value* / % Daily Value*
Total Fat0 g / 0% / Protein0 g / 0%
Cholesterol0 mg / 0% / Total Carbohydrate27 g / 9%
Sodium180 mg / 7% / Sugar(glucose and dextrose) 27 g
Potassium7 mg / 0% / Vitamin B-3 (niacinamide) / 100%
Vitamin B-12 (cobalamine) / 100% / Vitamin B-2 (riboflavin) / 100%
Other Ingredients: carbonated water,citric acid,natural flavors,taurine,sodium citrate,color added,panax ginseng root extract,L-carnitine,caffeine,sorbic acid,benzoic acid,niacinamide,sodium chloride,Glycine maxglucuronolactone,inositol,guarana seed extract,pyridoxinehydrochloride,sucralose,riboflavin,maltodextrin, andcyanocobalamin.
*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
You may want to look at a nutrition text book or website to identify the function of these vitamins.
WHAT IS THE FUNCTION OF THE INGREDIENTS IN MONSTER ENERGY DRINK?
We have talked in lecture about how caffeine can have psycological, diuretic, and possible cardiovascular effects. The effects of the other materials in all Energy Drinks are, honestly, much less clear cut. It is suggested that your lab group look these responses up in nutrition books, PubMed or just do a websearch.
In the language of researchers “Less Clear Cut” can be used to say that a function is not known or that opinions differ, sometimes these opinions can very widely between different researchers. Part of the exciting part of this lab is that you will be able to “characterize” the effect of a beverage whose actual physiological affects remain mostly uncharacterized. Think about it, over a billion cans of Energy Drinks were sold last year world wide, yet we know almost nothing about it. Indeed, there are very few peer-reviewed papers that have examined its affect (Baum and Weiss 2001; Alford, Cox and Wescott, 2001, Bichler Swenson and Harris 2006). Your lab instructor will have a link to three peer-reviewed papers that describe what its physiological affects really are. These and other papers sources you find on your own will be useful for preparing your laboratory write-up (see requirements later in this manual).
GOAL:This laboratory activity will compare the physiological effects of twodifferent treatment combinations. Each group will consist of 2-4 students. One student will be the volunteer test subject who will read and sign an informed consent document prior to starting the activity. The test subject then chooses the other members of their group. The test subject will need to abstain from all food and beverages other than water for 9 hours prior to study participation (this means no caffeine for 9 hours). The test subject will receive 3 points of extra credit (if in a lecture section of Drs. Wilson or Ragsdale), the other persons in the group will help by collecting data for their test subject. The group and test subject will then come to a special laboratory (Pasteur Room 106) early in the morning where they will be randomly assigned to one of two treatments. For this laboratory, you will either ride an exercise bike in the lab prior to consuming a Monster Energy Drink or there will be no prior exercise to consuming a Monster Energy Drink.
Volunteers will be assigned one of the following treatments:
1) A single serving ofMonster Energy drink without prior exercise
2) A single serving of Monster Energy drink with 10 minutes of prior work on exercise bike
HYPOTHESIS ABOUT HOW MONSTER AND EXERCISE AFFECT GLCYEMIC STATUS?
Consider the twoBEVERAGE-EXERCISE COMBINATIONS that we will test in this exercise (your subject will of course only complete one of the two). Will exercising have the same affect as not exercising before the test drink is consumed? Do you think the subject’s physiology will be affected differently in each of the twotreatment groups? Write a hypothesis for each treatment that summarizes your expectations and describe WHY you expect to observe a specific response for each treatment.
1) A single serving of Monster Energy drink without prior exercise.
Hypothesis and Why:
2) A single serving of Monster Energy drink with 10 minutes of prior work on exercise bike.
Hypothesis and Why:
Pre-experiment work:
Notes on Serving Size:The 240 ml (1 cup) standard serving size for the drink is adjusted up or down to match the subject’s weight. An average 168 pound subject consumes 240 ml. A weight-adjusted serving size is used to standardize serving size to body size. This way a short thin student of 100 pounds drinks less than a tall bulky 260-pound WSU football player,
Formula: Adjusted serving size = _____ml (Your wt lb)*(240mL/168 lb)
Notes on Exercise Intensity: To make the level of exercise equivalent for everyone: subjects will complete 10 minutes of exercise on a seated exercise bike at 33% of subjects Sex-Age-Weight predicted normal VO2 max. This is followed by 5 minutes of rest prior to consuming the Monster. This represents a standardized light level of aerobic work that should increase your sensitivity. Your exercise Bike RPM will be calculated by matching yourself to a fitness rating and running a mathematical calculation. In this way the level of exercise is higher for very fit persons and less intense for less fit persons, but equivalent relative to their predicted VO2 max:
VO2 Max Norms for College Aged Students: With 33% of Max values
Rating / 18-25 year olds Males / 33% of Max V02Above Average / 47-51 ml/kg/min / 16.17 ml/kg/min
Average / 42-46 ml/kg/min / 14.52 ml/kg/min
Below Average / 37-41 ml/kg/min / 12.87 ml/kg/min
Rating / 18-25 year olds Females / 33% of Max V02
Above Average / 42-46 ml/kg/min / 14.52 ml/kg/min
Average / 38-41 ml/kg/min / 13.03 ml/kg/min
Below Average / 33-37 ml/kg/min / 11.55 ml/kg/min
Bunc, V., & Psotta, R. (2001). Physiological profile of very young soccer players. Journal of sports medicine and physical fitness, 41(3), 337.
MET Calculation: VO2 = Sum of Resting + Horizontal + Vertical/Resistance
Monark Bike: V02 = (3.5) + (3.5) + (1.8 x work rate)/body mass(kg)
Work rate = ___in Kilogram meters per minute (Kg) x (Distance per revolution of Flywheel) X (Rev/Min)
~ Monark Bike has 6 m distance per revolution
A Biology Major working as Undergraduate Research Assistant will help you make these exercise and monster drink serving size calculations for your subject on the morning of the study.
The group assistants will measure their volunteer’s blood glucose, blood pressure, and heart rate, as well as collect the saliva sample at the beginning of the study prior to consuming the test beverage. The volunteer will be given the Monster Energy beverage to consume and these measurements will be repeated 30, 60, and 90 minutes after consuming the test beverage. The Energy Drink is only consumed once at the beginning of this study (0 minutes).
METHODS:
Approximately 100 volunteers will be asked to serve as the test subjects (randomized to one of the twotreatment combinations). The instructors will primarily recruit from their physiology classes, however other students may be invited to serve as volunteers for groups of Anatomy and Physiology students as long as they follow the rules outlined in this laboratory packet. Each volunteer will be asked to choose two to four students to help them complete the study. The student volunteer will read and sign the informed consent document with their group members serving as “witnesses”. The group will then be approved to sign up for a “special” study time on a Tuesday, Wednesday or Thursday morning. The start times will be staggered between 6am and 8am to limit the number of students inside the laboratory at any given time. The early start is needed because a 9 hour “fasting” pre-study period where participants will be unable to eat or drink anything except water is required (no caffeine allowed). You must also be able to complete the 9 hour fast without needing to take any medications that contain caffeine. Medications for colds and even some Tylenol products contain caffeine. We will not have normal lab hours this week, though the lab will be available for open lab work. Record all of your data on the report sheet attached to this laboratory: You keep one sheet for work on your laboratory report and hand the other sheet in when you are finished with the two-hour study period (5pts).