Science

In a single-blinded study, 16-week intervention with 550 mg DHA, 550 mg EPA, 10 µg vitamin D3, and 8 g whey protein twice daily demonstrated reduced total number of symptom days of upper respiratory tract infections (URTI) in young active people when compared to placebo. 

A total of 36 healthy and active individuals completed this study with the purpose of investigating the effect of a multi-nutrient supplement containing vitamin D, fish oil, and protein on the occurrence of URTI. 

Participants were assigned to consume either a multi-nutrient supplement* (intervention) or a carbohydrate-control** (placebo). Both drinks were unlabeled, and participants were blinded as to which drink they were assigned to. Participants consumed two drinks per day for 16 weeks and reported their physical activity levels and URTI incidences by a questionnaire. Additionally, unstimulated saliva samples were collected and analyzed for IgA (sIgA) concentration. Data were analyzed using the chi-square test, the independent t-tests, and the two-way repeated measures ANOVA.  

Results of the study showed that the number of symptom days was lower in the group who consumed the multi-nutrient supplement compared to the group who consumed the carbohydrate-control (Figure 1). No statistically significant differences were seen between the two groups in IgA concentration, and no differences were observed between the two groups in severity or duration of URTI among participants who reported an episode.  

In conclusion, results from this study indicate that a multi-nutrient supplement containing vitamin D, fish oil, and protein may reduce the total number of symptom days of URTI in young active people when compared to a control supplement of carbohydrate.  

Figure 1. URTI data from participants in control and supplemented groups of the 16-week intervention period.
An independent t-test was used to test for differences between the supplement group (n= 22) and the control group (n=20).  
*denotes a significant difference between the groups (P < 0.05).

*Multi-nutrient supplement:  
200 kcal, 550 mg DHA, 550 mg EPA, 8 g whey protein, 28,5 g carbohydrate, 10 µg vitamin D.
**Carbohydrate-control:  
Water, sugar, lingonberry juice (6.2 %), red grape juice (3.9 %), ascorbic acid, citric acid, and lingonberry aroma.  
100 kcal, 25 g carbohydrate, 0 g fat, and 0 g protein.

Da Boit M, Gabriel BM, Gray P, Gray SR. The Effect of Fish Oil, Vitamin D and Protein on URTI Incidence in Young Active People. Int J Sports Med. 2015;36(5):426-30.

In a double-blinded study, supplementing with fish oil, whey protein, leucine, and carbohydrate over six-weeks resulted in reduced muscle soreness after eccentric exercise in soccer players when compared to control supplements of protein or protein and carbohydrate.  

A total of 30 male competitive soccer players who participated in soccer training and/or match-play ≥3 times per week completed this study with the purpose of examining whether the addition of omega-3 fatty acids in a multi-nutrient supplement drink with whey protein, leucine, and carbohydrate affects recovery after eccentric exercise.  

Baseline data collected from participants included blood sampling for measurements of serum creatine kinase (CK) and plasma CRP concentrations, muscle soreness, muscle function, soccer skill tests, and anaerobic endurance. Participants reported perceived soreness 24, 48, and 72 hours after training using a validated visual analogue scale (VAS) scale.  

Included participants were assigned to consume one of three supplemental drinks for six weeks: a protein and carbohydrate supplement with omega-3 fatty acids (FO), a protein and carbohydrate supplement (PRO), or a carbohydrate only supplement (CHO) (Table 1).

FO: Protein and carbohydrate supplement with omega-3 fatty acids.
PRO: Protein and carbohydrate supplement.
CHO: Carbohydrate only supplement.  

Participants were instructed to consume two drinks per day while maintaining their habitual dietary intake and training load throughout the six weeks of supplementation. Participants and researchers were blinded as to which of the three drinks participants were assigned to (FO, PRO, or CHO).  

After six weeks of supplementation, data collected at baseline were recollected. The results of the study showed that the FO group had an increase in serum omega-3 PUFAs concentration after six weeks of supplementation, while no differences were observed in the PRO or CHO groups (Figure 1).  

Figure 2. Percentage of n-3 PUFA/total PUFA composition in blood before (Pre) and after (Post) six weeks of supplementation.
Group data expressed as M±SEM.  
*Statistical significant difference before and after supplementation in FO group (p <0.001).  
FO: Protein and carbohydrate supplement with omega-3 fatty acids.
PRO: Protein and carbohydrate supplement.
CHO: Carbohydrate only supplement.  

Additionally, the FO group experienced less dominant leg soreness after 24 and 48 hours compared to the PRO and CHO groups. Furthermore, dominant leg soreness was lower after 72 hours in the FO group compared to the PRO group. When measuring the entire time interval of 72 hours, general dominant leg soreness was 58% lower in the FO group compared to the CHO group (Figure 3A).  

Figure 3A. Muscle soreness of the dominant leg, expressed as raw values over time.  
Data are expressed as M±SEM.  
* FO significantly different versus PRO and CHO.
** FO significantly different versus PRO.
# Significantly different versus PRE in corresponding supplement condition.
FO: Protein and carbohydrate supplement with omega-3 fatty acids.
PRO: Protein and carbohydrate supplement.
CHO: Carbohydrate only supplement.  

Nondominant leg soreness was lower in the FO group compared to the CHO group after 24 hours. Similarity, the FO group experienced less nondominant leg soreness compared with the PRO and CHO group after 48 hours. The FO group experienced less nondominant leg soreness compared to the PRO group after 72 hours. General soreness of the nondominant leg over the entire 72-hour time interval was 58% lower in the FO group compared to the PRO group and 57% lower compared to the CHO group (Figure 3B).  

Figure 3B. Muscle soreness of the nondominant leg, expressed as raw values over time.  
Data are expressed as M±SEM.  
* FO significantly different versus PRO and CHO.
** FO significantly different versus PRO.
***FO significantly different versus CHO.
# Significantly different versus PRE in corresponding supplement condition.
FO: Protein and carbohydrate supplement with omega-3 fatty acids.
PRO: Protein and carbohydrate supplement.
CHO: Carbohydrate only supplement.  

Creatinine kinase concentrations, over the entire 72-hour recovery period, were lower in FO compared to CHO, and there was a tendency of lower CK concentrations in FO compared to PRO. 

In conclusion, this double blinded study demonstrates a decrease in perceived feelings of muscle soreness and a decrease in serum CK concentrations under fasting conditions in response to eccentric exercise when omega-3 fatty acids are added to whey protein, leucine and carbohydrate over a six-week supplementation period. No statistically significant differences were observed in muscle function, soccer performance, endurance, or serum CRP in any groups after the supplementation period. 

Abbreviations:  
FO: Protein and carbohydrate supplement with omega-3 fatty acids.
PRO: Protein and carbohydrate supplement.
CHO: Carbohydrate only supplement.  

Philpott JD, Donnelly C, Walshe IH, MacKinley EE, Dick J, Galloway SDR, et al. 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. 2018;28(1):26.

In this double-blinded study, consumption of Smartfish emulsion for four weeks increased carbohydrate oxidation and respiratory exchange ratio (RER) during moderate-intensity exercise in well-trained male cyclists and triathletes when compared to a control supplement containing protein, carbohydrate, and fat.  

Twenty-one male endurance-trained cyclists and triathletes completed this study with the purpose of investigating the effects of supplementing with omega-3 PUFA on metabolism at rest and during steady-state exercise. 

Included participants completed two experimental trials: one at baseline and one four weeks after supplementing twice daily with either a fish oil supplement (FO)* or a control supplement (CON)**. Participants were randomly assigned to consume one of the two supplements, and participants and researchers were blinded as to which of the two supplement they were assigned to.  

Data collected included heart rate, blood pressure, body composition, blood samples, lactate threshold levels, lactate turn point levels, Vo2 max scores, sub-maximal steady state scores, and resting energy expenditure (REE) using an indirect calorimetry.  

Additionally, participants completed a 3-day food and physical activity diary before the first set of data collection. Participants were asked to replicate this food intake diary 24 hours prior to the second experimental trial.   

Results from blood samples showed that the FO group had an increase in omega-3 fatty acids (EPA and DHA) in blood (Figure 1a and 1b). No changes in omega-3 concentrations in blood were seen in the control group.  

Figure 1a and 1b. Percentage of membrane EPA and DHA content Pre and Post supplementation.  
Data expressed as means ± SD.  
* FO had a significant increase Post supplementation compared to Pre supplementation (p<0.005).  

Furthermore, study results showed no observed differences between the two groups in measures of metabolism at rest. However, during moderate-intensity exercise, the FO group had an increase in respiratory exchange ratio (RER) (Figure 2a) and an increase in carbohydrate oxidation. No differences of carbohydrate oxidation were seen in the CON group (Figure 2b). The FO group also showed a decrease in fat oxidation, while no difference was observed in the CON group (Figure 2c).

Figure 2a. Respiratory exchange ratio during exercise.  
*Significant difference in Pre to Post changes between Fish Oil group (FO) and Control group (CON) (p=0.03).  
Values are presented as means ± SD.  

Figure 2b. Carbohydrate oxidation during exercise.  
*Significant difference in Pre to Post changes between Fish Oil group (FO) and Control group (CON) (p<0.05).  
Values are presented as mean ± SD.  

Figure 2c. Fat oxidation rates during exercise.  
*Significant difference in Pre to Post changes between Fish Oil group (FO) and Control group (CON) (p=0.07)
Values are presented as mean ± SD.  

In conclusion, results from this randomized double-blinded study report a significant increase in respiratory exchange ratio (RER) and carbohydrate oxidation in trained male cyclists performing steady-state exercise following omega-3 PUFA supplementation.  

*FO: 1 g EPA, 1 g DHA, 5 mcg vitamin D, 150 kcal, 4,8 g protein, 13,2 g carbohydrate, 8,2 g fat.

**CON: No fish oil, no vitamin D, 150 kcal, 4,8 g protein, 13,2 g carbohydrate, 8,2 g fat. 

Petre A, W. I., Dick J, Philpott JD, Tipton K, Macgregor LJ, Rodriguez-Sanchez N, Witard OC, Galloway SR. Substrate metabolism at rest and during steady-state cycling following four weeks of n-3 PUFA supplementation. Poster presented at: The American College of Sports Medicine; 2016; Indianapolis, IN.

Results from this double-blinded study show a large beneficial effect of Smartfish emulsion on increasing blood omega-3 PUFA concentrations and a moderate beneficial effect on lower body muscle soreness, fatigue, and countermovement jump (CMJ) performance compared to a control supplement containing protein, carbohydrate, and fat.  

The purpose of this study was to investigate the addition of omega-3 polyunsaturated fatty acids (PUFAs) to a protein-based supplement on muscle soreness, CMJ performance, and psychological well-being.  

A total of 20 professional Rugby Union players completed this study during their pre-season training. Included participants were randomized to consume 200 mL twice daily for five weeks of one of two supplements: fish oil (FO)* or placebo (P)**. Participants and researchers were blinded as to which of the two supplements participants received.  

Data collected included blood samples, muscle soreness using a 5-point-Likert scale, fatigue, sleep, stress, and mood using a questionnaire, neuromuscular fatigue by CMJ tests, and skinfold measurements. Data were analyzed using magnitude-based inferential statistics and were presented as percent beneficial/trivial/harmful. 

The results of the study show a very large likely beneficial effect of FO on increasing blood omega-3 PUFA concentrations (Figure 1) and a moderate beneficial effect on CMJ performance (Figure 2a), lower body muscle soreness (Figure 2b), and fatigue (Figure 2c) when compared to P. In contrast, trivial effects were found on sleep, stress, and mood. 

Figure 1. Omega-3 Polyunsaturated fatty acid (PUFA) concentrations (%) at baseline, day 19, and end (Day 35) for Fish Oil and Placebo. 

Figure 2a. Countermovement jump performance, expressed as mean (SD) percent change from baseline for fish oil (FO) and placebo (P) conditions during the 35-day period of pre-season training.
# Small standardized mean difference likely positive for change from baseline between fish oil and placebo.  
*Moderate, standardized mean difference between placebo and fish oil for change from baseline; likely beneficial, Day 16 (SMD: 0.89/10/1 likely beneficial): Day 35 (SMD: 0.60 moderate; 92/7/0 likely beneficial)
$ Moderate, standardized mean difference between placebo and fish oil for change from baseline; possibly beneficial  
Effect sizes were interpreted as trivial <20; small 0.20-0.59; moderate 0.60-1.19; large 1.20-1.99; very large 2.0-3.90; and almost perfect >4.00.

Figure 2b. Muscle soreness of lower body, expressed as mean (SD) change from baseline for fish oil (FO) and placebo (P) conditions during the 35-day pre-season training period.
*Moderate, standardized mean difference between placebo and fish oil for change from baseline; likely beneficial: Day 19 SMD: 0.71 moderate: 94/6/0 likely beneficial; Day 22 SMD: 0.60 moderate; 86/12/2 likely beneficial and Day 35 SMD: 0.75 moderate; 94/5/1 likely beneficial.
^Moderate standardized mean difference between placebo and fish oil for change from baseline; very likely beneficial: Day 16 SMD: 0.92 moderate; 97/3/1 very likely beneficial.
Effect sizes were interpreted as trivial <20; small 0.20-0.59; moderate 0.60-1.19; large 1.20-1.99; very large 2.0-3.90; and almost perfect >4.00.
A lower score represents greater soreness.  

Figure 2c. Fatigue score, expressed as mean (SD) change from baseline for fish oil (FO) and placebo (P) conditions during the 35-day period of pre-season training.
*Moderate, standardized mean difference between placebo and fish oil from change from baseline; likely beneficial.
$ Moderate, standardized mean difference between placebo and fish oil for change from baseline; very likely beneficial.
Effect sizes were interpreted as trivial <20; small 0.20-0.59; moderate 0.60-1.19; large 1.20-1.99; very large 2.0-3.90; and almost perfect >4.00.

In conclusion, this double-blinded study showed a large beneficial effect of Smartfish emulsion on increasing blood omega-3 PUFA concentrations and a moderate beneficial effect on lower body muscle soreness, fatigue, and CMJ performance. In terms of practical relevance, the moderate beneficial effect of adding fish oil to a protein-based supplement on muscle soreness translated into the better maintenance of explosive power in elite Rugby Union players during pre-season training. 

*Fish oil (FO): 1546 mg of omega-3 PUFA (551 mg EPA, 551 mg DHA), 15 g protein, 14.5 g carbohydrate, 8.4 g fat​

** Placebo (P): No omega-3, 15 g protein, 14.5 g, carbohydrate, 8.4 g fat​

Black KE, Witard OC, Baker D, Healey P, Lewis V, Tavares F, et al. 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. European Journal of Sport Science. 2018;18(10):1357-67.