Abstract
Purpose
Many athletes are deficient in long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA). A consequent low Omega-3 Index (O3I) and high arachidonic acid/eicosapentaenoic acid (AA/EPA) ratio increase cardiovascular disease risk and inflammation. Algae oil is a plant-based, sustainable source of LC n-3 PUFA, suitable for vegans and vegetarians. Effects of algae oil supplementation on whole blood fatty acids among athletes has not been previously reported. This study evaluated the effects of 5 weeks of DHA-rich algae oil supplementation on the whole blood fatty acid profile, O3I and AA/EPA ratio of omnivorous Division I American College Football (ACF) players. Methods: Data, including a spot blood sample, were collected at baseline for all participants (n = 47), then for a subset of players (n = 22) following a 5-week control period (usual diet) and 5 weeks of algae oil supplementation (usual diet + 1575 mg docosahexaenoic acid (DHA) + eicosapentaenoic acid (EPA) 5 days/week; average 1125 mg/day). Results: Baseline O3I was 4.3% ± 0.1% and AA/EPA ratio was 45.6 ± 23.8. After 5 weeks of algae oil supplementation, the O3I was 6.1% ± 1.0% and the AA/EPA ratio was 25.1 ± 11.6. The O3I was significantly higher and the AA/EPA ratio was significantly lower (P < 0.0001 for both) compared with both baseline and the end of the control period. The increase in O3I from baseline was correlated with calculated DHA + EPA dose per unit body mass (R = 0.641, P = 0.001). Conclusions: Algae oil supplementation for 5 weeks improved both the low baseline O3I and high AA/EPA ratio among ACF players, with body mass specific dose effects.
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Introduction
Many athletes [13, 42], including National Collegiate Athletic Association (NCAA) athletes [20, 43] and American College Football (ACF) players [4, 19, 37], are deficient in long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA). With effects of increased cardiovascular and muscle function efficiency, and reduced exercise-induced oxidative stress and inflammation [35], the LC n-3 PUFA are pertinent to all athletes, including ACF players. The International Olympic Committee (IOC) classifies LC n-3 PUFA as “supplements that may assist [the high-performance athlete] with training capacity, recovery, muscle soreness and injury management” [30]. In 2019, the NCAA by-law 16.5.2.7 was amended to include omega-3 fatty acids as permissable nutritional supplements [8]. The Academy of Nutrition and Dietetics recommended dietary intake of at least 500 mg/day of the essential LC n-3 PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) [41] can be accomplished by consuming 2 servings of fatty fish (8 oz; 225 g) per week. However, the majority of NCAA athletes [20, 43], including ACF players [1, 37] have inadequate dietary intake of fatty fish. LC n-3 PUFA supplementation with a plant-based algae oil rather than fish oil enables provision of the same supplement to all athletes in a team, whether omnivorous, vegetarian or vegan.
LC n-3 PUFA supplementation among athletes or physically fit individuals has positive effects on heart rate [27] and whole body oxygen consumption [21], reflecting enhanced cardiovascular efficiency. The Omega-3 Index (O3I), the percentage incorporation of DHA and EPA into red blood cell membranes, reflects the incorporation of LC n-3 PUFA into cardiac and skeletal muscle cell membranes [18] and is associated with cardiovascular disease risk. An O3I greater than 8% (desirable) is associated with the lowest risk of, and less than 4% (undesirable) with the greatest risk of, cardiovascular disease, including sudden cardiac death and myocardial infarction [18]. In three recent studies of ACF players, all participants had an O3I less than 8%, and one third had an O3I less than 4% [4, 19, 37].
LC n-3 PUFA supplementation can also attenuate skeletal muscle disuse atrophy [31], reduce muscle fatigue post-exercise [6, 26, 36], attenuate increases in neuroaxonal injury [19], and reduce eccentric exercise-induced delayed onset muscle soreness (DOMS) and inflammation [3]. These effects may be due to the associated changes in the PUFA n-6/n-3 ratio and inflammatory profile [22]. Metabolites of EPA and DHA are mostly anti-inflammatory, in contrast to the predominantly pro-inflammatory metabolites of the LC n-6 PUFA arachidonic acid (AA). An elevated AA/EPA ratio is a marker of chronic inflammation [33]. There are currently no established recommended levels for the AA/EPA ratio, and there is limited research on baseline AA/EPA ratios, particularly among athletes. Of the six publications to-date reporting the O3I among athletes, three did not report any n-6 PUFA data [13, 37, 43], and only two included the AA/EPA (or EPA/AA) ratio as a distinct measure [19, 42]. Among NCAA cross-country athletes, inflammation was the most and second-most common cause of injuries over a 4 year period for females and males, respectively [23]. Among healthy males, a higher baseline AA/EPA ratio was associated with greater loss of lean body mass after 5 weeks of inactivity [12]. Therefore, it is valuable to include the AA/EPA ratio alongside the O3I in LC n-3 PUFA supplementation studies among athletes.
DHA rather than EPA is selectively incorporated into skeletal muscle cell membranes [28] and associated with protection against concussion injury [34] and prevention of arrhythmias [32]. The latter is significant since arrhythmia is often a cause of sudden cardiac death among athletes [39]. Algae oil is a rich source of DHA, and algae oil supplementation is effective in improving a low or undesirable O3I in vegetarian and vegan adults [9]. Moreover, with inadequate fish sources to meet recommended LC n-3 PUFA intakes across the globe, algae, the main source of DHA in the marine food chain, is a viable and more sustainable source of LC n-3 PUFA [38].
The aim of this study was to evaluate the whole blood fatty acid profile, erythrocyte O3I, and AA/EPA ratio among Division I ACF players at baseline (consuming their usual omnivorous diets), after a 5-week control period during which subjects consumed their usual diet, and following 5 weeks of their usual diet plus supplementation with a DHA-rich algae oil. We hypothesised that ACF players would have a low baseline O3I and a high baseline AA/EPA ratio, and that 5 weeks DHA-rich algae oil supplementation would begin to ameliorate these.
Methods
Ethics Approval and Participants
Ethics approval was granted by the University of Wollongong Human Research Ethics Committee (Approval number: 2017/041) and the University of Oregon Institutional Review Board. Participants (all males) were recruited from the same National Collegiate Athletic Association (NCAA) Division I football team at the University of Oregon, prior to commencement of the 2017–2018 season. All participants provided informed signed consent prior to any data collection. The only exclusion criterion was current supplementation with LC n-3 PUFA, including fish and algae oil.
Study Design
Initially, cross-sectional data was collected during the first week of the pre-season period to gather baseline measures more broadly across the ACF team. A subset of these players volunteered to then complete a longitudinal study to determine the effects of 5 weeks supplementation with a plant based DHA-rich algae oil (Fig. 1). These players were age, weight and field-position matched with the remainder of the team, and each participant acted as their own control.
The longitudinal component of the study was 10 weeks in duration (the final 3 weeks of pre-season and 7 weeks of competition season), with each participant acting as their own control. This included a 5-week control period, during which subjects consumed their usual diet, followed by 5 weeks of their usual diet plus algae oil supplementation (Brain Amour, Inc). During the supplementation period, three soft gel capsules, providing a total of 1050 mg DHA and 525 mg EPA, were consumed with breakfast for the 5 weekdays of each week. This equated to an intake of 5.25 g DHA and 2.625 g EPA per week (equivalent to 750 mg of DHA and 375 mg EPA per day). A member of the research team provided each player with the algae oil capsules and supervised consumption to ensure compliance. During the entire 10-week study period, players were provided with all meals and snacks at the training facility as part of their college football scholarship, which ensured consistency in the usual diet across the control and supplementation periods.
The control period incorporated 3 weeks of pre-season training and the first 2 weeks of competition (Fig. 1). The pre-season training included 6 football practice sessions and 2 strength sessions per week. During the competition season, there was 1 game, 2 high intensity football practice sessions, 2 light football practices, an off day and 2 strength sessions per week. Throughout both the pre-season and competition seasons, players participated in approximately 12–15 h per week of physical activity.
Data and Sample Collection and Analysis
At baseline, age (years) was recorded, body mass (kg and pounds) and height (cm) were measured, and BMI was calculated. Systolic and diastolic blood pressure (mmHg) and heart rate (beats/min) were recorded in triplicate, while seated. Each participant’s BMI was classified as normal (BMI < 25 kg/m2), overweight (25 kg/m2 ≤ BMI < 30 kg/m2), or obese (BMI ≥ 30 kg/m2). Blood pressure was categorised as elevated (previously termed pre-hypertension) for systolic blood pressure 120–129 mmHg, and as hypertension for systolic blood pressure ≥ 130 mmHg or diastolic blood pressure ≥ 80 mmHg. A spot blood sample was collected at baseline for the whole cohort, and also at the end of each of the 5-week control and supplementation periods for those in the longitudinal study, for analysis of whole blood fatty acid profile, including percentage of relevant fatty acids, and calculated O3I and AA/EPA ratio.
The blood sample collection was performed using the dried blood spot method from each participant’s finger (OmegaQuant, South Dakota, United States). A lancet containing a spring-loaded needle was used to collect the blood spot on filter paper that was pre-treated with an antioxidant cocktail (Fatty Acid Preservative Solution, FAPS™), then allowed to dry at room temperature for 15 min. Samples were stored at − 80 °C and then fatty acid analysis was conducted using Gas Chromatography (Shimadzu Corporation, Columbia, MD) with comparison with a standard mixture of fatty acids characteristic of red blood cells (GLC OQ-A, NuCheck Prep, Elysian, MN). Whole blood fatty acid composition was expressed as a percent of total identified fatty acids. The O3I is defined as the sum of 20:5n-3 (EPA) and 22:6n-3 (DHA) adjusted by a regression equation (r = 0.97) to predict the O3I in the red blood cell [18].
Statistical Analyses
Statistical analyses were conducted using ‘Statistical Package for the Social Sciences’ (SPSS, Version 23). Values are reported with means and standard deviations. Comparisons between the subset of players who participated in the longitudinal study and the remaining players were made using one-way ANOVA with repeated measures and between groups analysis for anthropometric and fatty acid data, and with a Chi-square test for distribution of linemen versus non-linemen. For the longitudinal study, differences across time points (baseline, control and supplementation) were analysed using one-way ANOVA with repeated measures and post-hoc analysis with Bonferroni correction. Correlations are reported with Pearson’s correlation coefficients.
Results
Baseline Whole Blood Fatty Acid Profile
Baseline anthropometric and cardiovascular data are presented in Table 1. The mean age of the cohort was 20.8 ± 1.3 years. The majority of players were categorized as overweight (58%) or obese (33%) and had elevated blood pressure (45%) or hypertension (30%). Among the cohort of 47 players, the mean baseline O3I was 4.3% ± 0.1% and showed normal distribution (D(47) = 0.104, P = 0.200, Kolmogorov–Smirnov). All players had an O3I less than 8.0%, and one third (34%) had an O3I less than 4.0%.
Longitudinal LC n-3 PUFA Supplementation Study
There were no significant differences between the 22 players who completed the longitudinal study and the remaining players for baseline anthropometric data, or whole blood fatty acid profile [one-way ANOVA with repeated measures and between groups analysis; F(1) = 0, P = 0.992] or for distribution of linemen versus non-linemen (χ2 = 0.869, P = 0.351); hence they could be considered representative of the wider team. All O3I data points for the full cohort (n = 47) and the longitudinal study subset (n = 22) at baseline, and for the longitudinal study participants after the control and algae oil supplementation periods, are presented in Fig. 2.
Distribution of Omega-3 Index (%) for all ACF players (n = 47) at baseline and for participants in the longitudinal supplementation study (n = 22) also at baseline, and then after 5 weeks control and 5 weeks supplementation with 5.25 g DHA per week (averaging 750 mg per day). The Omega-3 Index was significantly different post-supplementation compared to both baseline and after the control period
When individual whole blood fatty acids were compared between the three time points (at baseline, and the end of the 5-week control and algae oil supplementation periods) for the longitudinal study, there was a significant effect for all polyunsaturated fatty acid measures except for total n-6 (Table 2). The O3I, n-6/n-3 ratio, AA/EPA ratio, total n-3 and DHA were each significantly different post-supplementation compared to both baseline and control time points (P < 0.0001 for all). EPA was significantly different between the control time point and following algae oil supplementation (P = 0.019).
After 5 weeks DHA-rich algae oil supplementation, the O3I significantly increased by one-third of the initial value and no participant had an undesirable O3I of less than 4%, with similar inter-individual variability to baseline and after the control period (Fig. 2). All participants except one (Fig. 3B) had an increase in their O3I after the 5-week supplementation period, with a mean magnitude of change of O3I of 1.4% ± 0.7%. Similarly, the AA/EPA ratio was significantly reduced by almost one-third of the baseline value after 5 weeks algae oil supplementation. The change in O3I was not correlated with baseline O3I (R = − 0.088, P = 0.698); however, the n-6/n-3 ratio pre-supplementation was inversely correlated with the change in the n6/n3 ratio after supplementation (R = − 0.664, P = 0.001).
When participants were classified into tertiles, based on body mass specific DHA + EPA dose (mg/kg body mass), there was a 1.5-fold difference between the lowest and highest tertiles. There was a greater than two-fold difference in the change in O3I with 5 weeks algae oil supplementation between the lowest and highest tertiles (Table 3). The body mass specific DHA + EPA dose was strongly correlated with both the O3I after 5 weeks supplementation (R = 0.548, P = 0.008; Fig. 3A) and the change in O3I from baseline until the end of the 5 weeks supplementation (R = 0.641, P = 0.001; Fig. 3B).
Discussion
In this group of ACF players, just 5 weeks of supplementation with a plant-based DHA-rich algae oil resulted in significant improvements in their low O3I and high AA/EPA ratio. The current results add to the few other studies that have reported on LC n-3 PUFA supplementation among ACF players, and demonstrate the effectiveness of supplementation with a plant based algae oil, providing DHA and EPA, in athletes. When body mass was taken into account, those with a higher supplementation dose relative to their body mass achieved the greatest changes in O3I. This DHA-rich algae oil supplementation, equivalent to approximately 2–3 fatty fish meals per week, was easily administered on training days (5 days per week).
All 47 ACF players in this study had a baseline O3I less than 8%, in the range associated with increased overall mortality, cardiovascular disease risk and depression [18]. The mean O3I was 4.3% ± 0.1%, and one third of players had an O3I less than 4% (undesirable), placing them in the highest cardiovascular disease risk category. The same mean and distribution were recently reported among three other cohorts of ACF athletes [4, 19, 37], and are similar to other athlete groups [13, 42, 43] and to the general USA population [40]. All players also had a high AA/EPA ratio, representative of a pro-inflammatory state. Although there are no established recommended levels for the AA/EPA ratio, the AA/EPA ratio of the current cohort of 45.6 ± 23.8 is well above the desirable range of 2.5–11 (OmegaQuant) and higher than other reports of: 20 in a large (n = 160,000) population of USA adults across the age-span [17]; 20–25 among athletes or physically fit males consuming a usual diet [27, 42]; and 30 in an ACF cohort [4]. Taken together, these results indicate that athletes, and ACF players even more so, have a high AA/EPA ratio, indicating their pro-inflammatory state and elevated risk of inflammatory diseases.
Among the subset of ACF players in the longitudinal aspect of the current study, 5 weeks supplementation with algae oil providing 5.25 g of DHA and 2.625 g EPA per week (equivalent to 750 mg of DHA and 375 mg EPA per day): significantly increased the low baseline O3I by approximately one-third, from 4.4% ± 0.6% to 5.8% ± 0.9%; and significantly reduced the AA/EPA ratio by almost one-third, from 34.1 ± 11.3 to 25.1 ± 11.6. This resulted in all participants achieving an O3I corresponding to a lesser risk of cardiovascular disease [18], albeit none were within the desirable range (O3I > 8%). This increase in O3I is of similar magnitude and end-point to previous research that also reported associated improvements in cardiovascular efficiency during exercise [21]. Achieving these physiologically relevant increases in O3I after only 5 weeks of supplementation is convenient with respect to the potential to improve any identified LC n-3 PUFA deficiencies in ACF players prior to the competition season. Interestingly, in the current cohort, the resultant O3I of almost 6% from a low baseline O3I (4.4%) after 5 weeks supplementation with approximately 1 g LC n-3 PUFA per day reflects the theoretical threshold effect for this DHA + EPA dose and baseline O3I [14]. This also suggests that the bioavailability of the LC n-3 PUFA provided by an algae oil is comparable to purified EPA + DHA and fish oil, since these supplementations were the basis for these theoretical projections [14]. Considering the low baseline O3I of athletes in the current study and the literature more broadly, initial supplementation with a higher daily dose of more than 2 g LC n-3 PUFA, before switching to a maintenance low dose (up to 1 g LC n-3 PUFA per day) akin to the current study seems practical, but will need to be followed up in subsequent studies.
Although the dose of LC n-3 PUFA in the current study can be obtained by consuming approximately 2 servings of oily fish per week, student-athletes with diets restricted to food service options on campus [24], and those with vegetarian or vegan dietary patterns [10] will require supplements to ensure adequate LC n-3 PUFA intake. Indeed, a recent study revealed that although 39% of 1528 NCAA athletes consumed the recommended amount of dietary fish per week, only 6% met the requirement for EPA + DHA intake [37], indicating that the fish sources were not adequate in terms of their LC n-3 PUFA composition. Similarly, the high AA/EPA ratios are indicative of consumption of a “Western” diet, high in red meat, dairy and eggs, and low in fatty fish. Further, the O3I of National Football League players decreased over the competition season [7], reinforcing the need for supplementation during the season.
Of relevance is that the effects of 5 weeks DHA-rich algae oil supplementation on the O3I post-supplementation and the change in O3I were dependent on LC n-3 PUFA dose per kg body mass, which was previously noted as a strong predictor of change in O3I [15]. The diverse body mass range of the current study participants, with an almost two-fold weight difference between the lightest and heaviest participants, is consistent with other ACF cohorts [16]. Extrapolation from the equation of the line for O3I post-supplementation plotted against LC n-3 PUFA dose per kg body mass (Fig. 3) suggests a minimum dose of 120 mg DHA + EPA/kg per week is necessary to achieve an O3I of 8% (desirable) within this time period of 5 weeks. This equates to a daily DHA + EPA dose of 1.37 g for an 80 kg player and 2.485 g for a player weighing 145 kg. Taking into account an individual’s weight is particularly important among cohorts of athletes with a large body mass range.
The low O3I and high AA/EPA ratio are particularly concerning because many of the ACF players in this cohort had additional cardiovascular disease risk factors: 91% had an overweight or obese BMI, and 75% had elevated blood pressure or hypertension. Without specific data on muscle mass versus adipose tissue, the use of BMI in this population is limited. Nevertheless, these results are in line with previous research reporting high BMI and body fat percentage [2], elevated blood pressure [11], and poor dietary habits [1] among ACF players. In addition, ACF student-athletes also experience mental stresses due to competing academic and sporting pressures, and there are concerns about the long-term mental health of athletes [29]. Low LC n-3 PUFA levels are associated with anxiety, depression and poorer quality of life measures [25]. Therefore, this represents a population who would benefit from LC n-3 PUFA supplementation to reduce modifiable risk factors for multiple diseases. Supplementation with LC n-3 PUFA aligns well with the focus areas for the well-being of collegiate athletes including “keeping hearts healthy”, “managing mental health”, and “fuelling performance” [5], with beneficial effects across all these domains.
The current study was limited in terms of a small sample size, a lack of physiological performance measures, and only omnivorous, male athletes being included. Inclusion of functional measures of cardiovascular and muscle performance, such as whole body oxygen consumption and muscle soreness, would increase the application of this research in athletic groups. Further, having BMI as the only measure of body composition without any data on the proportions of adipose and muscle mass to this measure is a limitation, particularly in an AFC cohort of diverse body fat and muscle percentage. Since adipose tissue is a storage site for fatty acids [15], it would be useful to assess its contribution to the body mass specific dose effect on the O3I. Inclusion of waist circumference as an estimate of central adiposity would also be beneficial. Further, it would be beneficial to assess the efficacy of algae oil supplementation among a more diverse athletic team, also including females, and vegetarians and vegans, and to gather data with respect to any side effects and acceptability of algae oil as a supplement.
Overall the results of this study demonstrated that a low and in some cases undesirable baseline O3I and high AA/EPA ratio in ACF players can be improved with 5 weeks supplementation of a DHA-rich algae oil. There was an influence of body mass specific dose on the effects of LC n-3 PUFA supplementation on both the resulting O3I and the change in O3I from baseline. This should be considered with respect to recommendations for LC n-3 PUFA supplementation to achieve a healthy O3I, which do not currently account for body mass specific dose effects or inter-individual weight variation. The provision of LC n-3 PUFA via an algae oil facilitates an opportunity to improve cardiovascular disease risk factors, cardiovascular and muscle physiology, and inflammatory status, in athlete groups who follow any of omnivorous, vegetarian or vegan dietary patterns. Such interventions are directly aligned with the focus of the NCAA and other athletic governing bodies on the health, wellbeing and nutritional status of these student-athletes.
Data Availability
Any/all data is available to reviewers and readers on request.
References
Abbey EL, Wright CJ, Kirkpatrick CM. Nutrition practices and knowledge among NCAA Division III football players. J Int Soc Sports Nutr. 2017;14:13.
Allen TW, Vogel RA, Lincoln AE, Dunn RE, Tucker AM. Body size, body composition, and cardiovascular disease risk factors in NFL players. Phys Sports Med. 2010;38(1):21–7.
Anthony R, Macartney MJ, Peoples GE. The effects of long chain omega-3 fatty acids on eccentric induced delayed onset muscle soreness: reported outcomes are compromised by study design issues. Int J Sports Nutr Exerc Metab. 2021;31(2):143–53 (In press).
Anzalone A, Carbuhn A, Jones L, Gallop A, Smith A, Johnson P, Swearingen L, Moore C, Rimer E, McBeth J, Harris W, Michelle Kirk K, Gable D, Askow A, Jennings W, Oliver JM. The omega-3 index in National Collegiate Athletic Association Division I collegiate football athletes. J Athl Train. 2019;54(1):7–11.
Association NCA. Well-being. 2018. http://www.ncaa.org/health-and-safety. Accessed 15 June, 2023.
Black KE, Witard OC, Baker D, Healey P, Lewis V, Tavares F, Christensen S, Pease T, Smith B. Adding omega-3 fatty acids to a protein-based supplement during pre-season training results in reduced muscle soreness and the better maintenance of explosive power in professional Rugby Union players. Eur J Sport Sci. 2018;18(10):1357–67.
Blue MN, Trexler ET, Hirsch KR, Smith-Ryan AE. A profile of body composition, omega-3 and vitamin D in National Football League Players. J Sports Med Phys Fit. 2019;59(1):87–93.
Autonomy. Proposal - awards, benefits and expenses—nutrition supplements - omega-3 fatty acids. 2019. Conference NB. Proposal Number 2018–119.
Craddock JC, Neale EP, Probst YC, Peoples GE. Algal supplementation of vegetarian eating patterns improves plasma and serum docosahexaenoic acid concentrations and omega-3 indices: a systematic literature review. J Hum Nutr Diet. 2017;30(6):693–9.
Craddock JC, Probst YC, Neale EP, Peoples GE. A Cross-sectional comparison of the whole blood fatty acid profile and omega-3 index of male vegan and omnivorous endurance athletes. J Am Coll Nutr. 2021;41(3):333–41.
Crouse SF, White S, Erwin JP, Meade TH, Martin SE, Oliver JM, Joubert DP, Lambert BS, Bramhall JP, Gill K, Weir D. Echocardiographic and blood pressure characteristics of first-year Collegiate American-Style Football Players. Am J Cardiol. 2016;117(1):131–4.
Di Girolamo FG, Agostini F, Mazzucco S, Situlin R, Mearelli F, Vinci P, Fiotti N, Biolo G. Baseline deficiency of the anti-inflammatory eicosapentaenoic acid in cell membranes worsens lean body mass wasting induced by inactivity. Clin Nutr Exp. 2017;14:36–41.
Drobnic F, Rueda F, Pons V, Banquells M, Cordobilla B, Domingo J. Erythrocyte omega-3 fatty acid content in elite athletes in response to omega-3 supplementation: a dose-response pilot study. J Lipids. 2017;2017:1472719.
Elagizi A, Lavie CJ, O’Keefe E, Marshall K, O’Keefe JH, Milani RV. An update on omega-3 polyunsaturated fatty acids and cardiovascular health. Nutrients. 2021;13(1):1–12.
Flock MR, Skulas-Ray AC, Harris WS, Etherton TD, Fleming JA, Kris-Etherton PM. Determinants of erythrocyte omega-3 fatty acid content in response to fish oil supplementation: a dose-response randomized controlled trial. J Am Heart Assoc. 2013;2(6):e000513.
Fullagar HHK, McCunn R, Murray A. Updated review of the applied physiology of American college football: physical demands, strength and conditioning, nutrition, and injury characteristics of America’s favorite game. Int J Sports Physiol Perform. 2017;12(10):1396–403.
Harris WS, Pottala JV, Varvel SA, Borowski JJ, Ward JN, McConnell JP. Erythrocyte omega-3 fatty acids increase and linoleic acid decreases with age: observations from 160,000 patients. Prostaglandins Leukot Essent Fatty Acids. 2013;88(4):257–63.
Harris WS, Von Schacky C. The Omega-3 Index: a new risk factor for death from coronary heart disease? Prev Med. 2004;39(1):212–20.
Heileson JL, Anzalone AJ, Carbuhn AF, Askow AT, Stone JD, Turner SM, Hillyer LM, Ma DWL, Luedke JA, Jagim AR, Oliver JM. The effect of omega-3 fatty acids on a biomarker of head trauma in NCAA football athletes: a multi-site, non-randomized study. J Int Soc Sports Nutr. 2021;18(1):00461.
Heileson JL, Elliott A, Buzzard JA, Cholewinski MC, Jackson KH, Gallucci A, Funderburk LK. A cross-sectional analysis of whole blood long-chain ω-3 polyunsaturated fatty acids and its relationship with dietary intake, body composition, and measures of strength and power in collegiate athletes. J Am Coll Nutr. 2021;42(1):94–100.
Hingley L, Macartney MJ, Brown MA, McLennan PL, Peoples GE. DHA-rich fish oil increases the omega-3 index and lowers the oxygen cost of physiologically stressful cycling in trained individuals. Int J Sport Nutr Exerc Metab. 2017;27(4):335–43.
Jeromson S, Gallagher IJ, Galloway SDR, Hamilton DL. Omega-3 fatty acids and skeletal muscle health. Mar Drugs. 2015;13(11):6977–7004.
Kerr ZY, Kroshus E, Grant J, Parsons JT, Folger D, Hayden R, Dompier TP. Epidemiology of national collegiate athletic association men’s and women’s cross-country injuries, 2009–2010 through 2013–2014. J Athl Train. 2016;51(1):57–64.
Kirwan RD, Kordick LK, McFarland S, Lancaster D, Clark K, Miles MP. Dietary, anthropometric, blood-lipid, and performance patterns of American college football players during 8 weeks of training. Int J Sport Nutr Exerc Metab. 2012;22(6):444–51.
Larrieu T, Layé S. Food for mood: relevance of nutritional omega-3 fatty acids for depression and anxiety. Front Physiol. 2018;9:01047.
Lembke P, Capodice J, Hebert K, Swenson T. Influence of omega-3 (N3) index on performance and wellbeing in young adults after heavy eccentric exercise. J Sports Sci Med. 2014;13(1):151–6.
Macartney MJ, Hingley L, Brown MA, Peoples GE, McLennan PL. Intrinsic heart rate recovery after dynamic exercise is improved with an increased omega-3 index in healthy males. Br J Nutr. 2014;112(12):1984–92.
Macartney MJ, Peoples GE, Treweek TM, McLennan PL. Docosahexaenoic acid varies in rat skeletal muscle membranes according to fibre type and provision of dietary fish oil. Prostaglandins Leukot Essent Fatty Acids. 2019;151:37–44.
Mann JB, Bryant KR, Johnstone B, Ivey PA, Sayers SP. Effect of physical and academic stress on illness and injury in division 1 college football players. J Strength Cond Res. 2016;30(1):20–5.
Maughan RJ, Burke LM, Dvorak J, Larson-Meyer DE, Peeling P, Phillips SM, Rawson ES, Walsh NP, Garthe I, Geyer H, Meeusen R, Van Loon LJC, Shirreffs SM, Spriet LL, Stuart M, Vernec A, Currell K, Ali VM, Budgett RG, Ljungqvist A, Mountjoy M, Pitsiladis YP, Soligard T, Erdener U, Engebretsen L. IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med. 2018;52(7):439–55.
McGlory C, Gorissen SHM, Kamal M, Bahniwal R, Hector AJ, Baker SK, Chabowski A, Phillips SM. Omega-3 fatty acid supplementation attenuates skeletal muscle disuse atrophy during two weeks of unilateral leg immobilization in healthy young women. FASEB J. 2019;33(3):4586–97.
Mozaffarian D, Wu JHY. (n-3) Fatty acids and cardiovascular health: are effects of EPA and DHA shared or complementary? J Nutr. 2012;142(3):614S–625S.
Nelson JR, Raskin S. The eicosapentaenoic acid:arachidonic acid ratio and its clinical utility in cardiovascular disease. Postgrad Med. 2019;131(4):268–77.
Oliver JM, Jones MT, Kirk KM, Gable DA, Repshas JT, Johnson TA, Andréasson U, Norgren N, Blennow K, Zetterberg H. Effect of docosahexaenoic acid on a biomarker of head trauma in American football. Med Sci Sports Exerc. 2016;48(6):974–82.
Peoples GE, McLennan PL. Fish oil for physical performance in athletes. In: RaatzFish SK, Bibusand DM, editors. Fish oil in health and disease prevention. Austin, Minnesota: Elsevier; 2016.
Philpott JD, Donnelly C, Walshe IH, MacKinley EE, Dick J, Galloway SDR, Tipton KD, Witard OC. Adding fish oil to whey protein, leucine, and carbohydrate over a six-week supplementation period attenuates muscle soreness following eccentric exercise in competitive soccer players. Int J Sport Nutr Exerc Metab. 2018;28(1):26–36.
Ritz PP, Rogers MB, Zabinsky JS, Hedrick VE, Rockwell JA, Rimer EG, Kostelnik SB, Hulver MW, Rockwell MS. Dietary and biological assessment of the omega-3 status of collegiate athletes: a cross-sectional analysis. PLoS ONE. 2020;15(4):e0228834.
Salem N Jr, Eggersdorfer M. Is the world supply of omega-3 fatty acids adequate for optimal human nutrition? Curr Opin Clin Nutr Metab Care. 2015;18(2):147–54.
Sweeting J, Semsarian C. Sudden cardiac death in athletes. Heart Lung Circ. 2018;27:1072–7.
Thuppal SV, Von Schacky C, Harris WS, Sherif KD, Denby N, Steinbaum SR, Haycock B, Bailey RL. Discrepancy between knowledge and perceptions of dietary omega-3 fatty acid intake compared with the omega-3 index. Nutrients. 2017;9(9):930.
Vannice G, Rasmussen H. Position of the academy of nutrition and dietetics: dietary fatty acids for healthy adults. J Acad Nutr Diet. 2014;114(1):136–53.
Von Schacky C, Kemper M, Haslbauer R, Halle M. Low omega-3 index in 106 german elite winter endurance athletes: a pilot study. Int J Sport Nutr Exerc Metab. 2014;24(5):559–64.
Wilson PB, Madrigal LA. Associations between whole blood and dietary omega-3 polyunsaturated fatty acid levels in collegiate athletes. Int J Sport Nutr Exerc Metab. 2016;26(6):497–505.
Acknowledgements
The authors would like to thank the players who participated in the study as well as Taylor Hughes, the University of Oregon Division I ACF team Dietician who helped with organizing and handing out the DHA-rich fish oil supplements to players.
Funding
Open Access funding enabled and organized by CAUL and its Member Institutions. John Sampson received grant funding for this study from the University of Wollongong.
Author information
Authors and Affiliations
Contributions
The study was conceptualised by JS, AM, BM, CP, NL and TL. Data were collected by BM and JD and analyzed by TL and JD. Statistical analyses and data interpretation were undertaken by TL. Manuscript preparation was undertaken by TL, GP and JS. All authors reviewed and edited the manuscript and approved the final version of the paper. JS was responsible for funding acquisition and oversight of the research.
Corresponding author
Ethics declarations
Conflict of Interest
Charles Pedlar is seconded to the position of Chief Science and Research Advisor, and Nathan Lewis is an employee, of Orreco Ltd. Orreco provided the OmegaQuant kits and analysed blood spot samples for this study. However, all samples were anonymised and the technicians who analysed the samples were never in contacted with any of the authors, were providing routine blood sample analyses only and were not aware of this study at all.
Ethical Approval
This study was performed in line with the principles of the Declaration of Helsinki. Ethics approval was granted by the University of Wollongong Human Research Ethics Committee (Approval number: 2017/041) and the University of Oregon Institutional Review Board.
Consent to Participate
Informed consent was obtained from all individual participants included in the study.
Consent to Publish
No individual data is included in this manuscript. All participants gave consent to have the aggregated results of the study published.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Larkin, T.A., McKay, B., Sampson, J.A. et al. A Low Omega-3 Index and High AA/EPA Ratio in American College Football Players are Both Improved Following 5 Weeks of DHA-Rich Algae Oil Supplementation. J. of SCI. IN SPORT AND EXERCISE (2024). https://doi.org/10.1007/s42978-023-00272-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s42978-023-00272-7