Potential constraints to the subject meeting the requirements
Due to the subject being a university student, there are many possible constraints to the subject meeting the recommended requirements. Ruiz et al, (2005) established that when people go to university (mainly athletes) or start work, the quality of their diet deteriorates. This could be due not only to a lack of time to eat healthily but finding the unhealthy options readily available and easy to consume. Financial issues play a big part within a student’s life and can be a key constraint to the subject not meeting the requirements. Other potential constraints for students include peers, lack of knowledge on the appropriate foods and the inability to cook healthy meals (Haberman & Luffey, 1998). Religion and food allergies can also provide limitations although this doesn’t apply for the subject. The student lifestyle generally includes a higher intake of alcohol due to social events and pressure from peers (Webb et al, 1996).
The aim of this investigation was to assess the subject’s nutritional intake and provide them with the appropriate information to help improve their diet. The subjects lifestyle and interests were important elements when interpreting the data and providing the correct interventions and dietary strategies to meet the clients specific needs.
Method
Subjects
The subject for the case study investigation was a 21-year-old male student from the University of Teesside. The subject’s height was measured using a SECA, UK stadiometre (1.78m) and weighed using the SECA, UK scales (65kg), consequently the subject had a BMI of 20.52 (kg . m-2). The subject was a member of the university men’s football team, which require participation in multiple training sessions and competitive games. The subject was considered to have moderately / very active lifestyle (Appendix 8) due to participating in daily gym sessions as well as university and semi-professional football. The university of Teesside ethics board approved the investigation prior to the data collection and dietary analysis.
Procedure
Written informed consent and a medical questionnaire were obtained after the purpose, nature and requirements of the project were explained to the subject. All information gathered during the investigation was keep confidential and filed away only to be accessible to the researcher. Anthropometric data in terms of mass (kg) and height (m) of the participant was recorded and the associated body mass index (BMI) (kg . m-2) was calculated. Skin fold measurements were deemed insignificant for the study, as the subject’s set goal was to improve soccer performance and not weight loss/gain.
Analysis
The subject completed a seven day food dairy, recording the amount and type of food / drink ingested. The completed food dairy was then analysed using the COMP-EAT software (Appendix 4 COMP-EAT Guidelines), this helped identify the client’s nutrient excesses and deficiencies. From the first COMP-EAT analysis (Appendix 5), the subject’s total energy expenditure and so requirement (Appendix 8) were calculated, along with the client specific macronutrient requirements (carbohydrates, protein and fats).
The software used calculates the absolute measure of the quantity of each nutrient (in grams etc) and the corresponding percentages. The reference dietary intakes adopted in the study are the recommended values for the general population by age and sex, without taking into account physical activity. From this data, the researcher was able to assess the client’s nutrient intake (deficiencies and excesses) and provide dietary strategies specific to the client’s current lifestyle.
The subject was given dietary interventions to help improve their nutrition and set specific goals to help rectify current problems and also meet the demands of their current lifestyle. The process was then repeated following the implementation of the chosen nutritional strategy aimed at helping the case study to rectify the problems identified during the first analysis. The strategy was then evaluated based on the data provided from the second seven-day food dairy analysed using the COMP-EAT software (Appendix 6). This second COMP-EAT analysis was compared to the pre intervention results to see if improvements had been made by the dietary modifications. The subject and researcher both discussed the nutritional strategies and agreed that to the goal was to help improve performance in soccer. Increasing the client’s macronutrient consumption as well as fluid intake along with a decrease in alcohol levels was agreed. The client however specified that no supplements would be implemented into the diet in order to help performance due to a personal choice.
Results
The COMP-EAT data showed the clients contributing foods, nutrient content and a summery of intake. From this data, the client’s nutrient content could be targeted and compared to the recommended nutrient intake (NRI), the client specific requirements (see appendix 7) and finally the results from the second COMP-EAT assessment after dietary strategies were put in place.
Figure 1. The total energy requirements / expenditure of the client
The graph shows the total energy requirements / expenditure amounts that the client ingested pre and post intervention compared to the RNI and the client specific energy requirements. The graph shows an increase in kcal from 1969 kcal in pre intervention to 2277.45 kcal post intervention. These results show the subject fails to meet the RNI (2860 kcal) and the client specific requirements (3681 kcal/ day) for energy requirement.
Figure 2. The subject’s carbohydrate, protein and total fat intake compared to the RNI and client specific requirements
The client consumed 158.4g of carbohydrates at pre intervention and increased to 280g after the nutritional strategies were put in place. However the subject still failed to meet the RNI amount of 285g and the client specific amount of 589g that takes into account the subject’s physical activity and sport completed. At pre intervention the client consumed 49.61g of protein, 89% of the recommended nutrient intake at 55g. However after the interventions had been set the subjects protein intake increased to 89.71g, consuming more than the RNI but still not meeting the client specific requirements of 138g. At pre-intervention the subject’s total fat intake was 77.69g, close to the recommended intake (RNI) of 72.2g. The subject showed an increase in total fat intake to 80g in post intervention, however the client specific requirements suggest that the client should have a total fat intake of 102.27g.
Figure 3. The total percentage energy derived from carbohydrates, protein, fats and alcohol.
The recommended energy intake should be provided from 60% carbohydrates, 15% protein and 25% fats. The subjects energy prior the to the interventions came from only 30.17% carbohydrates, 10.08 protein, 35.51 fats and 24.49 from alcohol. The subject showed an improving subsequent to receiving the interventions with 46.18% of energy coming from carbohydrates, 15.76% from protein, 32% from fats and only 6.27 from alcohol.
Figure 4. The subject’s element intake compared to the recommended requirements.
Figure 4 shows the elements that the subject was showing a deficiency in the recommended intake for selenium is 75mg, however the subject only consumed 7.86mg. Although after the nutritional strategies were set the subject showed a significant improvement by increasing the selenium amount to 43.49mg, yet still falling short of the recommended daily intake. The subject showed similar trends in iron, copper and zinc intake, presenting a low amount during the initial testing (7.87mg, 0.64mg & 4.9mg respectively) that didn’t meet the recommended requirements. In fact all three elements increased to go above the recommended requirements, with iron reaching amounts of 14.23mg, copper 1.52mg and zinc amounts of 10.5mg.
Discussion
It is clear from the data gathered in Figure 1 that the client was unable to consume the required amount of kcal’s to meet the demands of energy expenditure on a daily basis. As the case study has an active lifestyle, it was calculated that 3681 kcal was sufficient to meet the demands of the subject’s active lifestyle. However, the client was unable to meet the client specific target of 3681 kcal and only managed 2277 kcal after the interventions were implanted, showing much room for improvement.
Figure 2 shows that the subject recorded low levels of carbohydrates on the first test and was unable to RNI and client specific requirements for carbohydrates and protein. However the subject was able to the meet the RNI for total fat intake, therefore concentration on the other macronutrients was advised. With the dietary interventions in place the subject was able to increase the carbohydrates and protein amounts to meet the recommended nutrient intake and client specific requirements.
Figure 3 shows the percentage of energy accrued from each macronutrient at pre- post dietary intervention as well as the recommended percentages for the general population. The data shows that the subject’s percentage does improve due to the decrease in alcohol consumption although there is an issue in that there is still too much energy provided by fats that should be provided from carbohydrates.
Methodological limitations
The methodological limitations for the investigation came from a variety of sources. Firstly the food dairy given to the subject could show an incorrect representation of their diet due to either forgetting to record meals or making meals up. Human error also could be a limitation within this case study, whether it be when recording the height and weight measurements or using the COMP-EAT software. Also the equipment used could have been inaccurate, for example the scales may have not been calibrated to 0 or the subject not taking their shoes off for the height measurement. The COMP-EAT software however was the main source when considering methodological limitations as the software regularly failed to search the required food type, but also the quantity of the food provided would have made the results inaccurate due to the options being small, average or large. Therefore the COMP-EAT assessment would not be a true representation of the subject’s weekly diet. In terms of ethical content a written informed consent and a medical questionnaire were obtained after the purpose, nature and requirements of the project were explained to the subject. All information gathered during the investigation was kept confidential and filed away in a safe or password protected document only to be accessible to the researcher.
Dietary modifications
Consequently from the information gathered during initial testing (food dairy & COMP-EAT), it was apparent that dietary modifications needed to be implemented to improve the subject’s nutritional status. The subject and the researcher identified the aspect of implementing nutritional modifications to enhance performance in the subject’s sport (soccer) during the initial testing. Therefore the dietary modifications were implemented specifically to aid performance in soccer through the improvements in carbohydrate, protein, and fluid intake rather than additional supplements.
Soccer is a strength and power contact sport, involving high intensity activity, training and competition. Competitive matches involve intermittent high intensity sprints between periods of jogging and walking and repeated physical contact (Tumilty, 1993). Other than limits imposed by hereditary and training, diet is the single most important factor influencing athletic performance (Costill, 1986). Similarly Kirkendall (1993) demonstrated that good nutrition helps optimize energy production, control and efficiency for sport. Moreover, inappropriate nutrition may contribute to sport injuries (Eichner, 1995).
Soccer players train at moderate to high intensity, the estimated mean daily energy demand for senior male players had been estimated at ~4000 on training days and ~3800 on match days (Rico-Sanz, 1998). However Williams (1994) demonstrated that based on the assumption that energy expenditure off the football field is only moderate; the daily energy requirement of a male player can be estimated at 3500 kcal. day –1. Therefore the 1969 kcal consumed at pre intervention and the 2277.45 kcal consumed at post intervention would be classed as an insufficient amount of energy needed to participate in soccer training and competition. Although as the subject only plays at semi professional level of football, the 3800 kcal plus recommendations for professional’s athletes would be excessive for the subject.
The dietary strategies and interventions that were implemented involved an increase in energy expenditure, carbohydrates, protein and fats to meet the demands required from participation in football, as well as a decrease in alcohol and unhealthy snacks. Another dietary strategy that was high in priority was to increase the intake of fluids (water), as the subject was consuming insufficient levels of fluids, which can be issue, especially during exercise.
The energy sources exploited over the course of a soccer match are similar to those found in other types of intermittent exercise (Shephard, 1982). Depletion of glycogen in the most frequently recruited muscle fibres becomes a significant cause of fatigue as the game progresses, and performance can be enhanced by an initial boosting of muscle glycogen reserves (Bangsbo et al, 1992).
A high carbohydrate intake is recommended to maximise glycogen stores (Shephard, 1999). The dietary recommendation for soccer players, best expressed per kilogram of body mass, is 8 g. kg -1. day-1 (Devlin & Williams, 1993) or even as high as 10 g. kg -1. day-1 for endurance athletes (Graham, 2000). These amounts coincide with the client specific calculations with the requirement for carbohydrates being 589g a day or 9.02 g. kg -1. day-1. However the results illustrate that the subject was unable to consume the recommended carbohydrate amounts, even though showing an increase form pre to post intervention. Therefore for the subject to improve performance and nutritional status, an increase in carbohydrates s needed still, which could be in the form of pasta, rice potatoes, beans or sports drinks. McArdle et al (2005) suggests that a physically active person should get their carbohydrates from milk (16%), fruits and vegetables (47%) and bread and cereals (37%). As effective carbohydrate loading approximately doubles muscle glycogen stores, a recommendation for the subject would be to consume a high carbohydrate meal on the evening before a game to maximize glycogen stores. Glycogen loading results in a 5-6% increase in ability of adult players to make multiple sprints after the 45 min of simulated soccer (Bangsbo et al, 1992). Also literature suggests that a small dose of carbohydrate given shortly before a game may help spare muscle glycogen and maintain blood glucose (Tsintzus et al, 1993). Evidence also suggests that carbohydrate supplementation in male soccer players to decrease net muscle glycogen usage and enhance performance at the end of the match (Kirkendell, 1993).
Proteins are important molecules that serve structural and regulatory functions in the body (Tarnopolsky, 2004). The nutritional requirement for protein is the minimum amount ingested that will balance all nitrogen losses and thus maintain nitrogen equilibrium (Millward, 2001). Recommendations for protein intake usually amount to 0.8–1 g.kg–1 body mass. day–1 in adults without any reference to the undertaking of acute exercise or to the training status. However it is widely accepted that the World Health Organization’s recommended daily protein intake of 1 g.kg–1 body mass. day–1 is too low for athletes who undertake training (Lemon, 1994). Studies based on metabolic tracers and nitrogen balance techniques suggest that 1.2 – 1.8 g.kg–1 is more appropriate (Meredith et al, 1989), which coincide with the client specific protein requirements of 1.4 – 2.0 g.kg–1. Similarly Shephard (1999) states that 1.5 g.kg–1 is a sufficient protein intake for male soccer players.
Aside from obligatory uses, protein would be necessary for increased energy demands, protein synthesis of enzymes that are stimulated by intermittent exercise and, perhaps, repair of muscle proteins damaged by intense workout (Tipton &Wolfe, 2003). However client specific, team sports athletes, would consider protein requirements necessary to increase muscle mass and strength and power. Increased amino acid oxidation during exercise is thought to be due to increased utilization of amino acids as fuels; therefore regular repeated exercise would then lead to increased protein requirements (Tipton & Wolfe, 2003). However conflicting literature suggests that the opposite occurs, with exercise training increasing the efficiency of protein utilization, thus making increased intake unnecessary (Butterfield & Calloway, 1994; Todd et al, 1984). Similarly Gontzea (1975) demonstrated that that it is not necessary for physically active individuals to increase protein intake to maintain nitrogen equilibrium; in fact, exercise may decrease protein needs due to the increased efficiency of protein utilization.
The results show that the subject was unable to meet the protein requirements; therefore an intervention was put into place to increase the amount of protein ingested. An increase of protein in the body would help cover the demands of muscle repair and hypertrophy (Millward et al, 1994) that occur during physical activity and sport. With the subject’s goal in mind, mixed evidence has suggested that protein and amino acid ingestion is considered essential to performance (Tipton & Wolfe, 2003) and also inconclusive (Butterfield & Calloway, 1994; Todd et al, 1984; Gontzea, 1975)
After the initial testing, the subject’s fat intake was slightly above the recommended requirements but just below the client specific target. Therefore no dietary modification was needed, as other nutrients took priority. However the subject should continue monitoring food intake to ensure that the other interventions implemented do not interfere with fat intake.
Another dietary strategy that was implemented was that the subject was encouraged to take on more fluids and electrolytes daily. This was an important factor during the initial testing as the subject was consuming failing to meet the recommended intake of 3.7L/day (DRI, 2002). However conflicting evidence demonstrates that an intake of 2-2.5 L/day is sufficient fluid intake for the general population (Hicks, 2005), although this figure doesn’t take into account physical activity and the water lost through sweat. The metabolic heat generated by exercise must be dissipated to maintain body temperature within narrow physiological limits. When ambient temperature exceeds skin temperature, heat loss can occur only by evaporation of sweat from the skin surface (Shirreffs et al, 2003).
Dehydration symptoms generally become noticeable after 2 % of ones water volume has been lost and within the athlete population a loss of performance of up to 30% can be seen (Bean, 2006). Similarly it has also been well documented that even small body water deficits, incurred before (Sawka, 1992) or during (Cheuvront et al, 2003) exercise can significantly impair aerobic exercise performance, especially in the heat (Sawky, 1992; Cheavront et al, 2003). On the other hand Shephard (1999) states that if glycogen stores were to be fully depleted over a game, a player might lose 1.5-2.0kg of body mass without significant dehydration.
However more client specific, during soccer matches and training sessions, some players will lose considerable amounts of electrolytes – particularly sodium –and may need to replace these during the match or training session (Shirreff et al, 2003). From reviewing the literature the subject was advised to prepare a drink containing sodium, potassium and 5-6% of glucose or sucrose as it has a minor advantage over tap water in restoring balance after exercise (Lambert, 1997). Therefore if the subject was to continue participating in regular high intermittent exercise, severe dehydration may occur, which not only decreases aerobic power but muscular strength and endurance (Fogelholm, 1994) which makes everyday activities more difficult to perform.
The subject met the 100% requirement for most of the vitamins and minerals with the main deficiencies coming in iodine, selenium, copper, zinc and vitamin D. However it is important to note that the DRIs were not determined using athletes or regularly exercising individuals. In order for the client to reach the DRI for the previous stated elements, certain foods were identified. Dietary selenium functions as an antioxidant with glutathione peroxidase; complements vitamin E functions (McArdle et al, 2005) and can be found in nuts, cereals, meat fish and eggs (Barclay et al, 1995). However zinc is a component of several enzymes involved in energy metabolism; cofactor to carbonic anhydrase (McArdle et al, 2005) and is found in oysters, and to a far lesser degree in most animal proteins, beans, nuts and almonds but issues with finance would exclude the expensive options. Natural sources of iodine include sea life, such as kelp and certain seafood, as well as plants grown on iodine-rich soil. Vitamin D on the other hand can be found in milk, soy milk and cereal grains as well as exposure to sunlight.
Research suggests that no enhancement of physiological characteristics or performance after the administration of either vitamin (Van der beek, 1991; Fogelholm, 1994) or mineral (Clarkson, 1991; Similarly Shepherd (1999) demonstrated no benefit in male soccer player’s performance from vitamin or trace element ingestion. However vitamins have been proven to improve recovery after performance (Fogelholm, 1994).
Potential constraints to not meeting requirements for carbohydrates, protein and other nutrients could be due to the following factors. A significant majority of students reported eating the same foods day after day. Also student’s perceptions of diet or low calorie foods may limit their choices; a lack of cooking experience and time constraints may also have a negative effect on student’s intakes (Haberman & Luffey, 1998).
Alcohol
Alcohol is an energy-supplying nutrient that forms a small but important part of the normal dietary intake of a large part of the world’s population (Maughan, 2005). Due to the fact that the case study is a student, it is inevitable that a high consumption of alcohol is involved due to the social lifestyle and pressure from peers. However the most prominent reason for drinking within the university population was pleasure, which was more important than social pressure or stress/anxiety (Webb et al, 1996). This is confirmed by the first COMP-EAT assessment with alcohol providing 24.49% of the subject’s energy. Consequently the subject was given advice on the health risks of alcohol and recommended to reduce alcohol consumption as it would be impossible for the subject to completely stop due to the nature of the student lifestyle. A reason for the significant decline in alcohol consumption was due to the subject’s inability to afford alcohol.
If the client were to continue to lead an active lifestyle it would be advisable to further increase energy intake to the recommended requirements. It would also be suitable to increase carbohydrate intake, especially during exercise as it has been noted before to enhance performance (Bangsbo et al, 1992; Tsintzus et al, Kirkendell, 1993). With the literature on protein requirement and soccer performance varying in opinion, future recommendations would be down to the client’s personal choice. However it would be imperative for the client to improve fluid intake especially during exercise, as it can lead to serious health risks. It would also be advisable that that the client should decrease alcohol intake in the future due to the health risks involved however the student lifestyle can be a huge constraint to the client meeting these requirements.
Summary
The investigation shows that the subject increased the macronutrient intake for carbohydrate, protein and fats, although more still needs to be done in order for the client to meet the demands of an active lifestyle. The post intervention results show that carbohydrate amounts improved by 121g, proteins by 20.1g and fats by 7.8g. The subject showed improvements in fluid intake that has been known to be detrimental in performance enhancement (Sawky, 1992; Cheavront et al, 2003) as well as decreasing alcohol intake. The dietary modifications were imperative in terms of improving nutritional status and enhance performance although limitations due to student lifestyle will always play a negative part on nutritional status. Conversely the subject would still be advised to increase macronutrient intake in the future to meet the demands that soccer impose. Potential future research could focus on the dietary advice for the student population, including simple and cost effective stratagies to improve nutritional status.
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