Hydration and Recovery

In order to optimize athletic performance, it is essential to consume adequate amounts of fluid before, during, and after competition (ADA & ACSM, 2000).  Water is a vital component of life; it supports anabolic and catabolic cellular processes, regulates temperature, and it is a major component of the body, surrounding organs, tissues, and cells (ACSM 2007).  Maintaining fluid balance impacts reaction time, coordination, visual motor skills, arithmetic and mental capacity (Baker, Conroy, & Kenney, 2007). As a result, imbalances in fluid and plasma levels are associated with continuous impairments in performance and life threatening injuries, including heat stroke (Baker, Conroy, & Kenney, 2007; ACSM 2007).  During skeletal muscle contraction, as the core body temperature rises, the primary way to dissipate the heat is through sweat loss.  Hydration methods are dependent on the sweat response rates, which can be impacted by various factors including: environmental conditions, physical status, and equipment or clothing attire (ACSM 2007).  After competition, fluid ingestion should be adjusted to enhance gastric emptying, absorption, and the rate of recovery (Evans, Shirreffs, & Maughan, 2011).       

Total body water (TBW) concentrations averages about 60% of the body mass and concentrations are higher in muscle than adipose tissue.  As a result, trained athletes usually have higher muscle mass, lower body fat, and higher TBW concentrations than untrained individuals.  The body is composed of various fluid compartments, including extracellular, fluid between cells, and intracellular fluid, located within cells.  The kidneys maintain water balance and regulate extracellular fluid through urine excretion that ranges between 20 to 1,000 mL/h (ACSM 2007).  Within the body, the daily water balance is equivalent to the difference between water gain and water loss by metabolic processes  (Nolte, Noakes, & van Vuuren, 2010; ACSM 2007).  Water gain accounts for the production of water during substrate oxidation, exogenous ingestion of water containing substances, and during cellular metabolism, including the breakdown of glycogen stores in the muscle and liver (Nolte, Noakes, & van Vuuren, 2010).  During physical activity, metabolic heat is produced and transferred from the working muscles, to the blood, body core, skin, and then released into the environment through sweat glands.  Even though, sweat glands are able to reabsorb sodium and chloride concentrations, it is not proportional to the sweat rate so refueling of electrolyte and fluid levels are imperative (ACSM 2007).    

During exercise, the magnitude of fluid loss is influenced by exercise, ambient temperature, and individual characteristics, such as body weight, training status, and gender (ADA & ACSM, 2000).  The average sweat rate is between 0.5 and 2.0 L/h and electrolyte losses are related to the sweat volume and its electrolyte concentrations, especially sodium and chloride.  Heat acclimization actually improves sodium and chloride reabsorption and it is associated with lower sodium concentration for a given sweat volume, thereby enhancing the sweat rate  (ACSM 2007).  Sweating is a regulatory response for evaporative cooling so prolonged exercise in heated environmental conditions increases the core temperature, heart rate, and sweating response (Gonzalez-Alonso, Calbet & Nielsen, 1999).  In contrast, cooler temperatures would decrease the sweating response and slight dehydration in this environment would not impair the body to the same degree as in heat (ACSM 2007).  Dehydration suppresses heat dissipation and the sweating response, which overtime raises the body temperature and may cause heat stroke (Gonzalez-Alonso, Calbet & Nielsen, 1999).  Additionally, wearing heavy equipment and clothing may elicit high sweating rates, while wet skin suppresses this response.  Therefore, fully padded and high body mass football players produce an average of 8.8 L/d of sweat and runners sweat at a significantly lower rate of 3.5 L/d.  These heavy sweaters are susceptible to dehydration, electrolyte and sodium losses, fatigue, and skeletal muscle cramps (ACSM 2007).  Due to differing diuretic responses, sweating is impacted by gender and males usually have higher rates than females.  Females reduce circulating Arginine Vasopressin (AVP) concentrations in response to osmolality fluctuations and this may lead to elevated renal water and electrolyte loses (Evans, Shirreffs, & Maughan, 2011; ACSM 2007).

Dehydration is directly related to physiologic strain by altering cardiovascular, thermoregulatory, metabolic, and nervous system functioning  (ACSM 2007).  It is associated with faster rates of fatigue due to glycogen depletion, lactate production, and higher perceived exertion responses during exercise (Gonzalez-Alonso, Calbet & Nielsen, 1999; Baker, Conroy, & Kenney, 2007).  Only a 2% change in the body weight caused by dehydration is critical; it is associated with reductions in short-term memory, mental alertness, and fine motor skills, like eye-hand coordination (ACSM 2007; Baker, Conroy, & Kenney, 2007).  As a result of fluid and electrolyte imbalances: muscle contractions, blood volume, blood flow, nerve impulses, autonomic regulation of the heart, and even hormones may be altered.  Reduced blood flow supply within the body and to the skeletal muscle is associated with a reduced substrate delivery of free fatty acids (FFA).  This shifts energy utilization and causes increased lactate concentrations and glycogen utilization (Gonzalez-Alonso, Calbet & Nielsen, 1999).   

After exercise, the goal is to replenish all fluid and electrolyte losses and the ingestion of 1.5 L per kilogram of body weight lost is recommended.  In order to improve palatability of the fluid, the following components should be considered: temperature, sodium (20-30 mEq/L), and flavoring for taste (ACSM 2007).  In addition, the fluid volume, electrolyte concentrations, and the amount of macronutrients in the fluid replacement beverage, should be adjusted to facilitate gastric emptying and intestinal absorption.  Upon consumption, the rate at which the fluid leaves the stomach and enters the intestine is gastric emptying.  Gastric emptying is dependent on osmolality and high osmolality inhibits gastric emptying, while low osmolality promotes absorption.  The rate at which fluid is absorbed and carbohydrates and electrolytes enter the blood stream from the intestines is intestinal absorption and this is dependent on the type and amount of carbohydrates in the fluid (Evans, Shirreffs, & Maughan, 2011).  The optimal amount of carbohydrate for rapid fluid replacement ranges between 6-8% (30-80 g/h) and amounts greater than 8% will delay gastric emptying and compromise fluid replacement  (ACSM 2007).  Research by Currell and Jeukendrup suggest that the coingestion of multiple carbohydrate sources at one gram per minute is absorbed faster than one single source (2008). According to Table 1, the G-2 and Powerade Zero beverages are not sufficient in carbohydrates and the Gatorade Protein Shake exceeds the recommended percentage of carbohydrates.  The most expensive product is the Gatorade Protein Shake and it is the only beverage that contains multiple carbohydrates and has a ratio of carbohydrate to protein is three to one.  All of the other drinks supply adequate sodium and potassium amounts and are within the recommended range of carbohydrate percentage of 6-8%.

Table 1

Beverage	Calories	CHO	CHO (g)	Type of CHO	FAT (g)	PRO (g)	Na+ (mg)	K+ (mg)	Cost
Zinco (14 fl oz)	120	6%	24	Sucrose	2	1	140	600	$2.49
Powerade (12 fl oz)	80	6%	21	High fructose corn syrup	0	0	150	35	$0.89
G-2 (8 fl oz)	20	2%	5	Sucrose	0	0	110	30	~$0.89
Powerade Zero (12 fl oz)	0	0%	0	Sucralose	0	0	150	35	$0.89
Gatorade Protein Recovery Shake (11.16 fl oz)	270	13%	45	Maltodextrin, sucrose and sucralose	1	20	320	540	$2.69
Ideal Recovery Drink		~6%	14g	Combination of all types of CHO			100	28

Overall, sweat rates vary depending on the exercise mode, intensity, and other conditions.  In order to sustain performance, replacement of electrolytes and clued volumes is important to avoid the detrimental effects of dehydration.  The carbohydrate amount, fluid volume, electrolyte concentrations, palatability components, and osmolality of the fluid should be considered to enhance fluid absorption.  

References

American Dietetic Association (ADA) & American College of Sports Association

(ACSM). (2000). Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. J Am Diet Assoc., 100, 1543-1556.

American College of Sports Association (ACSM). (2007). American College of Sports

Medicine Position Stand: Exercise and fluid replacement. Med. Sci. Sports

Exerc.., 377-390.

Baker, L., Conroy, D., & Kenney, W. (2007).  Dehydration Impairs Vigilance-Related

Attention in Male Basketball Players. Med. Sci. Sports Exerc., 39, 976–983.

Currell, K. & Jeukendrup, A. (2008). Superior Endurance Performance with Ingestion of

Multiple Transportable Carbohydrates. Med. Sci. Sports Exerc., 40, 275–281.

Evans, G., Shirreffs, S., & Maughan, R. (2011). The effects of repeated ingestion of high

            and low glucose–electrolyte solutions on gastric emptying and blood 2H2O

            concentration after an overnight fast. British Journal of Nutrition, 106, 1732–1739. González-Alonso, J., Calbet, J., & Nielsen, B. (1999). Metabolic and thermodynamic

            responses to dehydration-induced reductions in muscle blood flow in exercising

            humans. Journal Physiol, 520, 577-589.

 Nolte, H., Noakes, T., & van Vuuren, B. (2011). Protection of total body water

content and absence of hyperthermia despite 2% body mass loss (‘voluntary

dehydration’) in soldiers drinking ad libitum during prolonged exercise in cool

environmental conditions. Br J Sports Med, 45, 1106–1112. 

The Effect of Creatine & Protein Supplementation on Basketball Performance

Section I: Introduction & Conceptualization of the Problem

Basketball is a highly intense anaerobic team sport that switches momentum every few seconds and combines mental stamina, skill, agility, power, and speed.  The majority of the fuel is derived from the simplest fuel system ATP-phosphocreatine (ATP-PCr) that anaerobically splits high-energy phosphates in the muscle, phosphocreatine (PCr), to rapidly release energy in the form of adenosine diphosphate (ATP) (Francescato, Cettolo, & Prampero, 2003; Pendergast, Meksawan, Limprasertkul, & Fisher, 2011).  The system is limited by PCr supply ranging from 17.8-37.7 mmol/kg, and within only a few seconds it is exhausted, and the other energy systems supplement the energy demands (Francescato et al., 2003).  During exercise, the rate of fatigue is linked to lactic acid accumulation, PCr concentrations, detrimental decreases in the pH that accompanies glycolysis and inhibits fat oxidation, and depletion of energy stores, especially glycogen (Coggan, 1997; Beneke et al., 2000; Meksawana et al., 2005).  Creatine (Cr) supplementation increases intramuscular PCr and is linked to increasing the power and capacity of the ATP-PCr system, while protein supplementation promotes an anabolic response to stimulate muscular gains (Rico et al.,).  Therefore, combining this ergogenic aid, Cr, with protein may be beneficial for basketball performance, altering body composition, and ultimately enhancing recovery.      

Highly intense exercise bouts are usually associated with microscopic tears in the muscle, tissue damage, suppression of the immune system due to high levels of cortisol, and net protein loss (Baty et al., 2007).  Catabolic hormones are released to degrade energy stores and amino acids account for less than 5% of the total energy (ADA 200; ADA 2009).  Since, the metabolism of protein and carbohydrates are intertwined, when blood glucose levels plummet, protein is supplemented through oxidation and protein synthesis remains either unchanged or decreases (Tipton et al., 2001).  Therefore, in order to optimize basketball recovery, the appropriate ratios of macronutrients, including carbohydrate and protein, is essential and must be consumed incrementally (ADA & ACSM, 2000; ADA 2009).  Dietary protein rich in amino acids, like whey protein, may help to promote an anabolic response by regulating synthesis in skeletal muscles, enhancing recovery, and suppressing catabolic hormonal release (ADA 2009; Tipton et al., 2001).  In a study by Tipton et al., after 45 minutes of lower body resistance training, the ingestion of essential amino acid (6 g) and carbohydrate (35g) stimulated anabolic hormones that shifted the net protein balance shifted to positive (2001).         

According to another study by Baty et al., male participants (n= 34) consumed either a placebo or carbohydrate-protein (CHO-PRO) supplement before, during, and after resistance training (2000). Within 24-hours, cortisol and creatine kinase (CK) was significantly elevated in the placebo group and the CHO-PRO group had significantly increased insulin levels.  The anabolic hormone, insulin, functions to promote glucose uptake into the cell through the GLUT-4 protein and certain branch chain amino acids (BCAA) activate glucose uptake through PI3-kinase.  After exercise, increased insulin levels optimize recovery by inhibiting protein breakdown and stimulating synthesis by promoting glucose uptake, glycogen synthesis through glycogen synthase activation, and tissue repair (Morifuji et al., 2010).  ).  Therefore, additional protein (1.2-1.7 g/kg/d) is recommended to optimize muscle gains and maintain the hypertrophic response to training.    

Creatine (Cr) supplementation has been shown to stimulate protein synthesis, delay fatigue, and improve ATP-PCr capacity, meaning an individual may be able to train at a higher volume.  Creatine monohydrate supplementation at 5-g per day for five days has shown to increase PCr stores by 20-30% (Journal of Clinical Scince, 1992).  In a study by Vandenberge et al., Cr supplementation paired with resistance training in healthy untrained women increased maximal strength in the lower body significantly by 20-25%.  At five weeks, fat free weight increased by 2.0 kg in the Cr group, while the placebo group only improved by 1.1 kg.  Acute creatine supplementation in elite female soccer players improved sprint performance and agility exercises with significant gains in body weight (Cox et al.).  While, competitive swimmer showed no significant increase in body weight after 9-days of Cr supplementation but saw improvements in sprint performance.  Nelson et al. (2000) found that Cr supplementation significantly improved GXT test time in trained adults with lower heart rates and VO2 measures.  Suggesting that during short-stage GXT testing, the increased PCr stores from the Cr supplementation could delay the aerobic metabolism reliance and ATP/ADP ratio, therefore yielding a lower VO2 value.

Research has shown that Cr may increase the size of the muscle fibers and further enhance training effects, including muscular strength and power performance.  According to a study by Burke et al., supplementation of Cr, whey, and Cr with Whey improved muscle strength and muscle mass.  However, coingesting Cr and whey had significantly greater lean tissue gains than in the whey or carbohydrate only group. 

Rational for the Project

The need of this project is to investigate the relationship of Basketball performance in female collegiate athletes after supplementation of Cr and/or whey protein.  To date, limited data has been reported with creatine supplementation in this population.  This investigation will help to develop a model for creatine and protein intake for female athletes by measuring anaerobic performance and body composition changes.  It will shed some light on creatine loading and protein supplementation on basketball performance. 

Statement of the Problem & Objectives

The purpose of the proposed study is to determine the impact of creatine and whey protein supplementation on body composition, sprint time, vertical jump, 1-RM leg press, and 1-RM bench press in collegiate female basketball players.  The specific null hypothesis is:

1.     There is no difference in sprint time, vertical jump, 1-RM leg press and 1-RM bench press among athletes after supplementation of creatine (Cr), whey protein and creatine (Cr+W) or glucose (P).

2.     There is no difference between muscle mass, and body fat percentage between Cr, Cr+W, and P groups.

Section II: Method

Participants

The participants were selected using a convenience sample of female athletes recruited from Texas Woman’s University (TWU) Basketball team.  All participants (n=15) were currently enrolled TWU students and attending off-season practice from Monday through Friday from 6:30-8:00am from March through May 2014.  The inclusion criteria was that the participants were: between 18-22 years old, live in the Denton area, and not taking any prescribed medication, ergogneic aids, or dietary supplements that would deter from the findings.  Participants were excluded if they had previously taken creatine, if they did not adhere to the protocol, and if any injury or health condition would interfere with the study.  Participants were randomly assigned to the following groups: (Cr) Creatine, (Cr+W) Creatine and Whey Protein, and (P) Glucose.  The Institutional Review Board (IRB) approved the study and all participants were informed of the objectives of the study and a written informed consent was obtained prior to the study. 

Instruments and Measurements

At baseline, a validated self-administered Medical History Questionnaire including family history, alcohol intake, and the use of any medications were recorded for each participant.  It provided demographic, personal history, contact and habitual information about the participants.  Afterwards, each participant met individually with a Registered Dietician (RD) at TWU’s Exercise Sports Nutrition Clinic to discuss the protocol, answer any questions and administer supplements, G2-Gatorade, instructions, and notebook to record timing of intake.  To ensure blinding, participants was given their individually wrapped and unmarked supplementation packets that were in the powder form.  Participants were randomly assigned to one of the following groups: creatine monohydrate (0.1 g/kg body mass/d), whey protein (1.2 g/kg of body mass) and creatine monohydrate (0.1 g/kg body mass/d), or  dietary carbohydrate (1.0-1.5 g/kg).  Each isocaloric supplement should be taken in four equal servings with 8-fl oz of G2-Gatorade within +30 minutes following morning practice (8:00 am), and then at lunch, late afternoon snack, and at dinner.  To ensure consistency, participants were reminded by the Assistant Coach, required to recorded the time of intake in the provided notebook, and received daily reminder through their TWU email account. 

In accordance with ACSM’s Guidelines for Exercise Testing and Prescription, height, and weight were measured.  The Salter 200 Academy Mechan Scale measured weight to the nearest 0.1 kg (without shoes or heavy apparel) and height was recorded to the nearest 0.5 cm (without shoes).  Body composition, muscle mass and fat mass, was measured by the gold standard Dual-energy X-ray absorptiometry (DXA) scan.  Whole body scans were performed on bone densitometer Norland XR-36 and body tissue was analyzed with Software 3.7.4 Version 2.1.0 (Norland Corporation, Ft. Atkinson, WI).  All scans were performed according to the standard protocol with participants in supine alignment.  Following each scan, the tester performed a standard calibration. 

In accordance with ACSM’s Guidelines for Exercise Testing and Prescription, vertical jump, 1-RM leg press, and 1-RM bench press was measured.  The 1-RM leg press was tested on the Standard Leg Press Machine and the 1-RM bench press was tested on the Standard Bench Press.  Subject warmed-up by completing submaximal repetitions.  After a brief warm up, each participant determined the 1-repetition maximum (1-RM) within four trials with rest periods between 3-5 minutes.  To determine the participant’s ability, the first initial weight was between 50%-70% of perceived maximum.  After the first trial, weight should be increased by 2.5 to 20 kg.  This step was repeated until the participant could no longer lift the weight.  The largest weight lifted successfully is the final result and recorded as the absolute 1-RM.  With the subject standing with their feet flat on the floor with either shoulder next to the wall, reach as high as possible on the wall and record to the nearest cm.  Bend at the knees and then thrust forward at upward touching the highest point on the wall.  Repeat the test three times and record the highest value.  The difference between the standing reach value and the vertical height is the vertical jump height to the nearest cm (McArdle, Katch & Katch). 

On the following day, sprint time was measured by sprinting across ¾ basketball court (75 feet or 22.86 meters) and two testers recorded times using digital stopwatches. Sprints were repeated four times with a 5-minute passive recovery followed by 10-15 minute rest between intervals.

Procedures

The study was 14-days long and prior to the study, the participants were recruited and coaches were informed of the study. At baseline, a Medical Health Questionnaire was completed and then participants were randomly assigned to a supplement group, and consulted a RD.  Following an overnight fast (12-14 hours), weight, height, and the whole body DXA scan were measured at baseline.  On the next day, the participants performed 1-RM bench press, 1-RM leg press, and vertical jump.  Then one the following day, timed sprints were completed.  The participants were reminded Monday through Friday about the study at practice, received daily reminder from their TWU email account, and all received detailed instructions detailing the protocol.  After the 14-day supplementation interval, notebooks were collected and following an overnight fast (12-14 hours), weight, height, and whole body DXA scans were measured. Then on the next day, the participants performed 1-RM bench press, 1-RM leg press, and vertical jump.  Then on the next day, each participant performed timed sprints.    

Approximate Timetable of the Study

·      January 2013-Febuary 2014: Recruitment begins for the test.  Participants were screened to meet the inclusion criteria.  Then, each completed an Informed Consent and Medical Health Questionnaire.  The introduction and method sections were completed.

·      Febuary-March 2014: Receive permission for administering DXA scans during the upcoming months at the Exercise Sports Nutrition Clinic.  Select the Student R.D. that will assist the study and attain all the supplies for the study.

·      March-April 2014: Participants were randomly assigned to treatment group.  Then met with the RD and completed baseline measures: DXA, height, weight, and muscular strength and power measures. 

·      April 2014: Participants continue practice regimen and follow supplementation protocol for 14-days.

·      April 2014-May 2014: Complete follow-up measures, including: DXA, height, weight, and muscular strength and power measures. 

·      June 2014-July 2014: Complete analyses and perform statistical analyses

·      August 2014-November 2014: Write the results and discussion of the manuscript.  

Design and analysis

The results are expressed as means + SDs or medians and interquartile ranges are specified.  The level of significance was set at 0.05 to make decisions about the hypothesis. Statistical analyses were conducted by SPSS version 13 (for Windows).  Associations between changes were assessed with the Spearman correlation coefficients.  The analysis of variance (ANOVA) compared the three groups and changes in body fat, muscle mass, muscular strength (1-RM leg and bench press), vertical jump, and sprint time in the groups: (C) Creatine, Creatine and Whey (Cr+W), and Glucose (P).  Linear trends were used to test any relationship between creatine intakes, changes in body composition.

Significance of the Project

            Limited research has been conducted examining the responses of Cr, Cr+Whey, and Glucose supplementation in collegiate female basketball players to strength and power performance, muscle mass, and body fat.  More over, the quantifications of these distributions following 14-days of loading has not been reporting in this population.  This investigation will address a unique and important question regarding Cr and/or Whey protein supplementation are strongly associated with basketball performance: what are the body composition and athletic performance responses following 14-day of loading in female basketball players. 

Proposed Method of Presenting Results

First, an abstract of results and conclusions of this investigation will be submitted to the ACSM annual meeting.  Second, they will be submitted to a peer-reviewed journal publication. 

 

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