In Part 3 of “Understanding environmental and societal factors in effort to develop effective methodology and solutions for weight management in elite football athletes” we will evaluate the various relationships between weight gain and football athletes and complete the foundation for an effective methodology to weight management for elite football athletes.
It seems reasonable to expect that a rise in energy dense, nutrient poor, highly processed foods along with reports of increases in both child and adult obesity reported both nationally and worldwide may also be reflected in individuals who engage in the sport of football.
Researchers from the University of Minnesota investigated the relationship between sport participation and diet and found that sport participation is associated with more fast food, sugar sweetened beverage consumption and greater overall calorie intake (Nelson et al., 2011). Additionally, there is evidence to demonstrate both a predisposition towards obesity as well as increase in fat mass in certain sports – namely football. A cross-sectional study on athletes in the state of Mississippi single-sport football players demonstrated a statistically significant increase in the prevalence of obesity when compared with single-sport athletes in other sports (Stiefel et al., 2016).
This finding is reflective of the similar rise in waist lines noted in the public (and detailed in part 2). One can argue that as the average weight of the public has risen over the years, the average weight of football players has also increased over the years. Take a look at the historical changes in weight in one of the most imposing figures on the football field – The offensive linemen. Data published by researchers in 2013 shows that the average body mass of an offensive lineman has increased by more than 66 lbs over a 45 year period (Anding & Oliver, 2013).
Today’s NFL athlete is far larger, heavier and stronger than years past. A 2013 research study evaluated 411 NFL athletes just before the 2013 NFL draft or selection period for NFL teams. The following values represents and insight into today’s NFL athlete (Dengel et al., 2014).
The Body Composition and Anthropometric values for today’s NFL athlete are as follows.
Average Height: 75 + 1.1 inches
Average Weight: 293.0 ± 32.4 lbs
Average Body Fat: 25.2 ± 7.6 %
Average Lean Mass: 209.9 ± 12.1 lbs
Average Fat Mass: 73.4 ± 27.1 lbs
Average Height: 75.9 ± 1.6 lbs
Average Weight: 310.6 ± 13.4 lbs
Average Body Fat: 28.8 ± 3.7%
Average Lean Mass: 212.7 ± 9.9 lbs
Average Fat Mass: 86.6 ± 13.2 lbs
Average Height: 73.1 ± 1.5 lbs
Average Weight: 207.2 ± 13.2 lbs
Average Body Fat: 12.5 ± 3.1 %
Average Lean Mass: 172.6 ± 9.5 lbs
Average Fat Mass: 24.9 ± 7.7 lbs
Authors report that an increase in body mass or height is associated with increased playing time as well as greater rates of pay in football (Anding & Oliver, 2013). When we combined the financial incentive for mass gain, with a current climate involving both environmental and/or societal factors (food industry/food distribution) that helps to facilitate weight gain, the results can be a challenge for both athletes and the individuals tasked with managing their weights. While the thought that “Bigger is always Better” continues to prevail in certain sports, evidence may prove otherwise.
One must also consider that a relative increase in fat mass, can predispose individuals to injury and degradations in performance. This is due to evidence which shows that fat-free mass has a direct correlation with performance measures including strength, speed and explosiveness (Anding & Oliver, 2013). In other words, it’s not good not to have just bigger athletes but we also want bigger athletes with better body composition. The objective for athletes have always been to decrease percentage body fat by simultaneously decreasing fat mass and increasing lean body mass. In addition to increasing on-field fatigue, increases in fat mass can contribute to the development of metabolic syndrome, which includes impaired glucose tolerance, dyslipidemia and hypertension. Excess body fat also contributes to obstructive sleep apnea, vitamin D deficiency and cardiovascular disease (Skolnik & Ryan, 2014).
Limitations in the amount of time for which these football athletes can train presents another “difficulty” for weight management during off – season training.
While the establishment of resistance and conditioning programs has allowed for increases in measures of strength, power and body composition there are limitations to the degree and duration of impact for which these training programs can have on athletes. For instance, the NFL Collective Bargaining Agreement, a contract between NFL players and owners, allows a relatively limited training period that promotes the interaction of football athletes with team Strength and Conditioning programs (NFL collective bargaining agreement, 2011). NFL players can report voluntary to meet with strength and conditioning coaches for a period of roughly two weeks prior to engaging in football athletics. Interaction between strength and conditioning coaches and athletes prior to this two-week period must operate in a limited “supervisory” fashion. The results of this limitation in strength training and conditioning combined with the aforementioned environmental and societal factors that contribute to weight gain can provide a challenge for the potential detraining effects that are characteristic with both long competitive seasons as well as “Break” periods from the NFL. It should not be surprising then that the off-season period (a period of extended can be a difficult period of time for athletes to maintain body composition.
Body composition changes may be the most important manner for which athletes can manifest improvements in performance.
It’s also important to revisit the relative importance of body composition changes in the NFL to the improvement of athletic performance. Since the majority of athletes are gathered from the highest level of function in football collegiate sports we can infer that these athletes are likely to have four or more years of resistance training history and have come close to their peak of training. Studies note that performance measures in factors such as speed, power and vertical jump can significantly improve within the first two years of a collegiate strength and conditioning program with no significant changes thereafter suggesting that athletes can reach a training limit from strength and conditioning training in certain measures related to athletic performance (Jacobson, Conchola, Glass & Thompson, 2012). In fact, researchers in health and human performance from the University of Oklahoma suggested that speed cannot be significantly improved in collegiate athletes over 4 years of training. In a 2013 longitudinal study published in the Journal of Strength and Conditioning, football Collegiate linemen saw just a 2.7% increase in speed performance. This change in linemen speed was positively correlated with a reduction in fat (Jacobson, Conchola, Glass & Thompson, 2012).
Additionally, football players chosen to participate in football’s highest level are likely to have a minimum of two years of collegiate football experience due to the NFL draft requirements. The rules of the NFL draft indicate that for an individual to be eligible for the draft, players must have been out of high school for at least three years and must have used up their college eligibility before the start of the next college football season (The rules of the Draft, 2018). Moreover, in 2009 greater than 80% of athletes selected in the NFL draft were participants of the NFL combine, a standardized assessment where NFL teams consider a player’s performance on a set of physical ability tests. (Lyons, Hoffman, Michel &Williams, 2011). The rising number of combine preparation programs demonstrate both the value of performance training for success within this event but also underscores the high training age of athletes who make up the NFL performance fabric. This evidence serves to highlight the relative importance of body composition change as a notable and useful method to provide meaningful change to football athletes in preparation for a competitive season. If two years of training is enough time for which collegiate athletes need to reach high levels of physical performance than further improvements in performance and injury must be mediated by a centered focus on body composition.
NFL player body composition changes over an NFL season
Few studies have examined the nutritional intakes of NFL players over the course of a season and its influence on body composition and long-term performance. Understanding the impact of nutrition and training during the period of preparation prior to competition can be of significance to an athlete’s potential for high short term and long-term performance.
To understand this importance, it is important to review, a typical NFL season. By the time a season ends, NFL athletes are likely to “take time off”. And rightly so, as a traditional NFL training season can last well over 36 weeks when we accrue various training periods such as training camp, off Season training, regular season and playoffs. This can result in large physical and mental toll to athletes. Thus, a time away or off from football is certainly justified as it allows athletes to physical and mentally recover. However, this time off or potential period of detraining can result in devastating changes to levels of fitness and pose a challenge for those individuals accustomed to the daily training regimens involved during a football season.
For instance, just five weeks of detraining produced significant changes to body composition, fitness and metabolism in competitive collegiate athletes. These Athletes also saw increases in fat mass, waist circumference and body weight as well as reductions in measures of aerobic performance (Ormsbee, & Arciero, 2011). Keep in mind that NFL detraining periods or “time off” can last from anywhere from two to four months depending on team success. Highly successful teams will account for more weeks of training due to their participation in post season competition while less successful teams will begin their break at the inception of the post season. Additionally, teams will also issue “Break” periods prior to the start of the Pre-season or Training Camp period prior to the competitive season.
Interestingly, several investigations show that the preseason period provides the greatest risk for soft tissue injury. In a 2011 study, Elliot and colleagues showed that the first weeks during a competitive football season also known as the preseason period can place football players at increased risk for soft tissue injury. In fact, More than half (51.3%) of hamstring strains occurred during the 7-week preseason (Elliott, Zarins, Powell & Kenyon, 2011). This data become increasingly relevant when we consider that competitive teams have an incentive to quickly return to a level of performance that can allow for voluminous practices and opportunities to evaluate and/or development skills related to high performance.
The incentive to prepare returning athletes to proper shape can often fall on the shoulders of NFL strength and conditioning staffs. However, the NFL collective bargaining agreement (CBA) allows just two weeks of uninterrupted training with strength and conditioning staffs prior to the introduction of competitive football practice conditions dictated by various football coaches. This can result in a formidable challenge for both strength and conditioning professional and athletes when we consider
1. Reports for rising rates of obesity in children, adults and football players
2. Evidence which suggests the proliferation of highly processed foods for increases in weight gain and obesity.
3. Data demonstrating rising rates of mass in NFL athletes and evidence for the increasing role body composition plays to NFL performance.
These results help to shape a methodology which can provide an effective solution for performance athletes in the face of these challenges. In particular athletes utilizing the methodology of body composition change through diet may provide useful in mitigating injury and alleviating the difficult associated with weight management in today’s society.
The use of low carbohydrate as well as the Ketogenic diet to improve body composition during the “off-season” or “Break” period for Football athletes.
The ketogenic diet can be a useful resource for a number of athletes who are interested in improving factors related to athletic performance thereby diminishing chance of injury and increasing likelihood for football success. This particular diet contributes to positive changes in weight loss such as diminished fat mass. The dietary protein needs associated with the diet may also assist in promoting improved performance through protective effects of fat free mass.
Investigators from the University of Padova publish a study in 2012 where their objective was to determine if a very low carbohydrate Ketogenic Diet (VLCKD) could be useful for elite athletes without negative changes to measurable in performance and certain body composition values such as lean muscle mass (Paoli et al., 2012).
Their study included nine male athletes competing in several portions of Italy’s highest level of gymnastics. The workload for this group of individuals was tantamount to that expected for elite professionals with a training volume averaging of 30 hours a week. These athletes were asked to keep to their normal training volumes while consuming a very low carbohydrate Ketogenic diet for 30 days. Performance measurements relating to force and strength were measured through a litany of tests that included various forms of jump testing, and upper body strength assessments such as dip tests, Pull ups Tests, and push up tests(Paoli et al., 2012). The use of a contact mat known as Ergojump provided a measurement of height of jump, time of flight and time of contact. Investigators also measured body composition, through an equally comprehensive battery of tests. These tests include 9 skinfold measurements, 6 bone diameters (elbow, wrist, knee, ankle), waistline and hip circumference measurements. It should be noted that air plethysmography through tools such as COSMED’s Bod Pod and/or dual energy x-ray absorptiometry are highly regarded as accurate measures of body composition these tests were performed as pre testing and post testing protocols and occurred at the beginning and end of the 30 day very low carbohydrate ketogenic dietary periods. During the 2nd investigation the athletes took part in a western diet and served as controls (Paoli et al., 2012)).
Results of the study showed that there was a significant difference in the pre-testing and post testing of the very low carbohydrate ketogenic diet in body weight with a change from a mean weight of 69.6 ± 7.3 Kg to 68.0 ± 7.5 Kg with a significance of p< 0.05. In addition, values showed that fat mass changed from 5.3 ± 1.3 Kg to 3.4 ± 0.8 Kg with a significance of p< 0.001. Body Fat Percentage change was reflected with a pre – test value of 7.6 ± 1.4 to a post test value of 5.0 ± 0.9 with a significance of P< 0.001(Paoli et al., 2012). In comparison to the body composition value change during the very low carbohydrate ketogenic dietary period, athletes showed was no significant difference in body composition when comparing pre testing and post testing while consuming a Western Diet(Paoli et al., 2012).
The results of this study suggest how a very low carbohydrate ketogenic diet can impact fat loss and may be useful for those athletes who compete in sports based on weight class. Authors of this study, acknowledged these conclusions. In spite of concerns of the potential detrimental effects of low carbohydrate diets on athletic performance. In a more recent study published in Journal of Sports, investigators sought to understand the effects of a 12-week ketogenic diet on body composition, metabolic, and performance parameters in participants who trained recreationally at a local CrossFit facility (Kephart et al., 2018). These researchers noted several previous investigations which supported the use of ketogenic diet for improvements in body composition, muscle mass and strength with notable reductions in fat mass.
As part of this study, twelve subjects were recruited from a local CrossFit gymnasium a local Auburn community. Subjects were selected based on a particular criterion that included age, strength to mass ratio, and training age at the local cross fit center. The experiment consisted of ketogenic diet group and a normal western diet group. It should be noted that the cross-fit community has been associated with a relatively low carbohydrate diet known as the paleo diet. Thus, it should be specified what diet control members utilized within this study. The Ketogenic group were provided dietary guidelines to follow over 12 weeks while CTL participants were instructed to continue their normal diet throughout the study. All participants continued their normal CrossFit training routine for 12 weeks. Measurements for this study included body composition, blood variables and various performance tests. Body composition was evaluated using a dual X-ray absorptiometry. Researchers, keenly evaluated for levels of hydration prior to conducting body composition. Using a hand-held refractometer participants with a urine specific gravity ≥ 1.020 were asked to consume tap water every 15 min for 30 min and then were re-test. To demonstrate the great deal of evaluations performed in this test, investigators also assessed Respiratory Energy Expenditure and VO2 max post body composition. Venous blood assessments included blood glucose, lipids, and beta-hydroxbutyrate (BHB). Performance measurements included 1 RM Back Squats, Power Cleans, a Push Up test and a 400-meter sprint test. These measurements were likely selected due to the likely familiarity that comes from training in a CrossFit manner, however to complement these values and to reflect more objective measures of performance tools such as a just jump or force plate could have been used. Limitations can also be seen in the form of dietary monitoring. Subjects were required to record and report food logs. Food Logs are a subjective form of assessment and can be largely inaccurate to true both nutrition composition and intake (Kephart et al., 2018).
Results of the study were neatly arranged and detailed. Researchers reported a time interaction was observed for change in fat mass between groups (p = 0.126, ηp2 = 0.218. DXA fat mass decreased by 12.4% in KD (p = 0.058). In regard to profile changes, researchers reported similar changes in fasting glucose, HDL cholesterol, and triglycerides between groups. However, it should be noted that LDL cholesterol increased ~35% in KD (p = 0.048). Lastly, performance measurements Between-groups showed similarities in one-repetition maximum (1-RM) back squat, 400 m run times, and VO2peak (Kephart et al., 2018). Researchers appeared to meet the aim of their study with some limitations. They reached a conclusion that individuals who train recreationally at a CrossFit gym while adopting a Ketogenic diet for 12 weeks experience a reduction in whole-body adiposity with little influence on metabolic or exercise performance measures. The reports provided by these authors helps to highlight the useful application of ketogenic diets as a resource to reduce fat mass while facilitating improvements in performance measures (Kephart et al., 2018).
Relationship of Ketogenic Diet to measures of performance: Increased protein intake and fat free mass
Researchers Michael J. Saunders and Colleagues recently published an article titled “Protein Supplementation During or Following a Marathon Run Influences Post-Exercise Recovery” in the Journal Nutrients (Saunders, Luden, DeWitt, Gross & Rios, 2018). These authors address various finding related to the ingestion of carbohydrate and protein and its effects on post-exercise recovery in endurance athletes. They begin by describing the past evidence which demonstrates a positive relationship between protein supplementation and post exercise performance markers such as reduced muscle soreness, creating kinase, myogoblin and enhanced mood. This information is followed by a relatively limited amount of contrary evidence to the positive effects of carbohydrate protein supplementation. The ambiguity in findings likely stems from experimental methods as reported by these authors. However, the purpose of their study aims to study the effects of carbohydrate and protein ingestion on a specific population. These author aim investigate the efficacy of carbohydrate and protein in specific sport populations, in order to provide appropriate recommendations for endurance athletes (Saunders, Luden, DeWitt, Gross & Rios, 2018).
As part of this study, authors recruited subjects from the university. These subjects were both male and female with no history of marathons using a similar training program to prepare for an upcoming marathon. Subjects were divided into two groups based on muscular responses from a training run taken in the 11th week. Experimental groups consisted of a carbohydrate group and a carbohydrate and protein group. As part of the study both groups were provided their corresponding nutritional sources at a fixed number of aid stations along the marathon course. These subjects were instructed to consume gels ab libitum and thus were not required to consume all of the nutritional aids offered. Therefore, each individual is likely to experience variability in the nutritional intake during the marathon which can impact markers of recovery and thus represents a limitation to this study.
This is apparent within the results of the study. Investigators demonstrate that the carbohydrate only group consumed 4.5 ± 1.4 gels during the run, resulting in 123 ± 36 g CHO ingested (0 g protein, 0 g fat). However, the carbohydrate protein group consumed 5.9 ± 1.5 gels, with 118 ± 29 g CHO, 29 ± 7 g protein during the run. As a result, the protein intake during the marathon was higher in the carbohydrate + protein group(Saunders, Luden, DeWitt, Gross & Rios, 2018). As a result the calorie intake is likely to be larger in one particular group as compared to another which can potentially impact level of exertion, markers of muscle damage and levels of soreness. In fact, the authors indicated within this study that although carbohydrate + protein ingestion during the marathon had no meaningful effects on any recovery markers 24 h post-exercise, in comparison to carbohydrate, differences were observe at 72 hours post marathon. Investigators indicated that at 72 h post-marathon, various ratings of soreness and mental and physical energy/fatigue were reduced in the carbohydrate protein group versus the carbohydrate only group. These results highlight the importance of protein in its role as a resource to decrease levels of soreness and physical energy/fatigue. It also suggests how valuable protein may be in the beneficial effects of ketogenic diet to performance. This positive finding attributed to protein intake can also be shown during periods of significant energy deficits (Saunders, Luden, DeWitt, Gross & Rios, 2018).
Researchers from Spain conducted a study to examine the role of exercise volume and dietary protein content. In particular they sought to understand the influence of low-intensity exercise and/or protein ingestion on lean mass during severe energy deficit diets (Calbet et al., 2017). The foundation for this study rests on several investigations presented by researchers which demonstrate that very low calorie diets result in both loss of fat, but also loss of fat-free mass. Investigators randomly assigned 15 overweight volunteers to receive 0.8 g/kg body weight/day of either whey protein or a similar amount of calories in the form of sucrose during 4 days of extreme energy deficit. As part of the experimental study these overweight subjects participated in a baseline phase, followed by 4 days of caloric restriction and exercise and then followed by 3 subsequent days on a control diet in combination with reduced exercise (Calbet et al., 2017).Various measurements were taken during this experimental protocol such as body composition, Peak power, VO2 and blood analysis. Results of the study showed that Lean body mass was reduced from 64.3 ± 4.9 at baseline to 61.5 ± 4.7 and 63.3 ± 4.5 Kg calorie restriction and during the control diet. These comparisons were exhibited with a significance of P < 0.01). Additionally, measurements of peak power after the controlled eating portion were 15 and 12% lower than the corresponding baseline values. This was exhibited by a change from 300 ± 23 to 254 ± 25 watts and a change from 84 ± 0.33 to 3.37 ± 0.43 L/min. These changes were exhibited by a significance of P < 0.01. As part of this discussion, authors stated that their findings demonstrated a clear impact of exercise in its ability to preserve lean mass, even with an energy deficit and significant dietary protein exposure (Calbet et al., 2017).
Consider an athlete with a moderate volume and strength program that helps to maintain the needed strength associated with performance. A six to twelve-week low carbohydrate, high fat and/or ketogenic dietary program focusing on a macronutrient content that provides calories from 19 % carbohydrate, 26 -30% protein and up to 65% fat can be a useful resource prior to training. This can be especially suitable for individuals who are unlikely to participate in voluminous, high intensity fast pace running drills for which a higher carbohydrate intake can be of greater need.
Let us consider the 300lb offensive linemen once more. Due to the nature of the “Break” period he no longer takes part in two to three hour long football practices. With his activity level at a relative low he no longer needs a surplus of calories to maintain both performance and body mass. Thus he shifts his caloric intake to 3200 calories with 10% resulting from the consumption of carbohydrates 30% protein and 60% fat. He spreads this daily need into 5 meals which elicits 80 grams of carbohydrates, 300 grams of protein and 213 grams of Fats. An example meal for this particular diet can be shown in a meal containing the following: ½ cup of chopped avocado, 4 scrambled eggs, sautéed spinach and smoked salmon.
The result of such a meal and diet can provide athletes and strength and conditioning coaches a useful tool and path toward improved body composition and performance. In today’s climate of rising obesity associated with the challenges that come with performance training at the elite level, tools like the ketogenic can offer tremendous and long lasting benefit.
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