This study aimed to evaluate Omega 3 Chia seed loading as a means of enhancing sports performance of distance runners. Omega 3 Chia seeds are a rich and unprocessed whole food source of Omega 3 fatty acids. They contain all the essential amino acids and are high in antioxidants. They are also rich in fiber and absorb up to 10 times their weight in water allowing the slow absorption of sugar into the body. Omega 3 Chia seeds were prized by ancient Aztec warriors as an endurance promoting food, eaten with bread just before battle, and drunk with water before running long distances on foot (14).
Carbohydrate (CHO) loading has been used for approximately 40 years to enhance the performance of athletes in events lasting >90 minutes. There are many forms of CHO loading, but recent research has shown that 8 g·kg−1·d−1 should be consumed to enhance performance (1,17,18). All other things being equal, endurance athletes who can store more muscle glycogen will have some advantage over an athlete who cannot and who exhausts muscle glycogen stores earlier.
Research has supported the benefits of a high-fat diet over a high-CHO diet for enhancing an endurance athlete's performance because a high-fat diet can increase fat utilization and glycogen sparing, but research has also noted that the rating of perceived exertion is higher with a high-fat diet than with very low-CHO diet (17). Sherman et al. (16) reported that a 20.9-km run by trained endurance athletes with a high-CHO diet (70% CHO) used significantly more glycogen compared to a moderate CHO diet (50% CHO) but made no difference in performance run times or postperformance glycogen levels. They also reported that “muscle glycogen can be elevated to high levels with a moderate exercise-diet regimen (50% CHO)”. Studies done to compare high-fat diets to high-CHO diets have shown that with a high-fat diet there is a significant increase in fat oxidation during exercise and thus a reduced CHO usage (3-5,8,10,13).
By using Omega 3 Chia seeds as a CHO-loading method, athletes may be able to increase their fat oxidation while sparing muscle glycogen compared to traditional CHO loading. Because “muscle glycogen can be elevated to high levels with a moderate exercise-diet regimen (50% CHO)” and Omega 3 fatty acids may increase fat oxidation, it seems logical that a drink of Omega 3 Chia seeds (50% cals) and CHOs (50% cals) may prove to be a more beneficial source of fuel for endurance performance lasting >90 minutes (16). It was hypothesized that Omega 3 Chia loading would be more beneficial than traditional CHO loading because its high fat and moderate CHO might improve endurance fuel usage.
Experimental Approach to the Problem
To examine the hypothesis that Omega 3 Chia loading may be more beneficial than traditional CHO loading, 6 highly trained endurance athletes were recruited to participate in this investigation. Only men were employed in this study because there is recent evidence that CHO loading does not occur in the same manner for men and women, thus affecting performance and possibly confounding testing results (18). The study was based upon the CHO loading strategy that has shown that a combination of a short-term bout of high-intensity exercise followed by a high-CHO intake enables athletes to attain supranormal muscle glycogen levels (6). Subjects were asked to perform a high-intensity workout 2 days before testing and were then required to drink either an Omega 3 Chia loading drink (Greens Plus, Vero Beach, FL, USA) or a CHO-loading drink (100% Gatorade) for 2 days before an endurance performance trial. The CHO-loading drink was used as the control drink because there is a large amount of scientific evidence that shows CHO loading to be superior to water before endurance events lasting >90 minutes. Carbohydrate loading should exceed 8 g·kg−1·d−1 to increase muscle glycogen stores, which has been shown to lead to performance benefits often seen in events lasting >90 minutes in duration (1,15,16). Because each subject was encouraged to eat like they normally do, the investigators calculated the drinks so that they were isocaloric and consisted of 6 g·kg−1·d−1 per athlete. This assumed that each subject obtained 2 g·kg−1·d−1 of CHOs from his daily food. Food logs were taken to insure that each subject met the minimum intake of CHO of 8 g·kg−1·d−1.
Two weeks before performance trials, testing was done to assess each participant's V̇O2max. All subjects performed a maximal bout of running on a treadmill. Each subject wore a heart rate (HR) monitor (Model FS3 Polar, Kempele, Finland). There was a 3-minute warm-up with a gradual increase in speed. During the rest of the test, speed was increased every 2 minutes until the subject reached 8 mph. At this point, elevation was increased by 1% every 2 minutes until a 3% incline was reached. After 3% incline was attained, the speed was increased by 0.5 mph every 2 minutes until the subject reached maximal oxygen uptake. Rate of perceived exertion was recorded every 2 minutes. During this protocol, HRs were recorded every minute. This data allowed us to replicate a corresponding HR of ∼65% V̇O2 max during our performance testing. This protocol was continued until each subject reached his maximal oxygen uptake or until the subject could not perform any longer. To ensure that the subjects reached maximal oxygen, they were required to meet 2 of the following criteria: (a) attaining their predicted maximum HR, (b) a respiratory exchange ratio (RER) >1.17, (c) or the subject reached a plateau of oxygen consumption while exercise intensity increased (12). Each subject was verbally encouraged to work to his maximal capacity.
On the day of performance testing, the subjects ran 1 hour at ∼65% of their V̇O2max (as assessed by HR) on a treadmill followed by a 10k time trial on a track. This was done to create a controlled competitive endurance event that lasted >90 minutes. There were 2 trials in a crossover counterbalanced repeated measures design with a 2-week washout between testing sessions to allow the participants to recover from any effects of the intense exercise and the treatment. The experimental design is displayed in Table 1.
Six subjects (6 men) with V̇O2max values that varied from 47.8 to 84.2 ml·kg−1, and a mean (SD) V̇O2max of 70.3 ml·kg−1 (13.3). The subjects varied in age from 20 to 34 years. Mean (SD) subject physical characteristics were as follows: age 23.67 (5.2) years, height 196.7 (8.7) cm, weight 68.2 (8.5) kg, mean personal best for 10k was 35 minutes 55 seconds.
The Chia seeds used for this study were Omega 3 Chia seeds (Greens Plus, Vero Beach, FL, USA) and were certified kosher and pesticide-, herbicide-, gluten-, and genetically modified-free.
This study was approved by the local Institutional Review Board for the Protection of Human subjects, and written consent was obtained from all subjects before the collection of any data.
Three days before testing, participants were given a food intake log and were reminded of the training protocol and asked if they needed any clarification on procedures.
Two days before testing, the participants were required to complete an intense run on their own between 5 and 9 am. They were instructed to do intervals runs alternating periods of high intensity with low intensity, and the workout could not last >60 minutes. Immediately after their run, they were given a drink mix that they could drink ad libitum throughout the day. The amount of drink that each participant was given was based on his body weight and was isocaloric, regardless of the treatment. For example, a participant weighing 68 kg (170 lbs) would drink 1 of the 2 drinks below (1 each trial): (a) CHO drink (Gatorade Original Powder, Barrington, IL, USA) = 1,636 cals from simple CHO; (b) Omega 3 Chia loading drink = 820 cals from Greens Plus Omega 3 Chia seeds plus 820 cals from CHO drink (Gatorade).
Each drink for this participant would be 1,636 cals, and he would be required to drink that throughout the day. The Chia drink (50% Greens Plus Omega 3 Chia seeds, 50% Gatorade) and the control drink (100% Gatorade) were isocaloric.
One day before the test, the subjects were instructed to do only light exercise before 9 am or to rest completely. They were also required to pick up a drink mix (identical to the one they received the day before). Each participant was asked to have the drink mix finished by 9 pm the night before the test. This encouraged frequent feedings and reduced possible digestion problems associated with a change in diet.
On the day of the test, all subjects reported to the testing site at 6 am. They were given a prerun questionnaire. Each subject was only allowed to drink water during the test performance. The test consisted of a 1-hour run at ∼65% of their V̇O2max on a treadmill, followed by a 10k time trial on a track. To assess ∼65% of their V̇O2max on the treadmill, the investigators matched HRs with each subject's HR during V̇O2 max testing. Each subject wore an HR monitor (Model FS3 Polar, Kempele, Finland). Subject were required to keep his HR within 5 beats ± of the HR that was assigned to them associated with 65% of their V̇O2max. After the 1-hour run at ∼65% of their V̇O2max on a treadmill, the subjects did a 10k time trial on the track. All 10k times were recorded. After the test, each participant filled a postrun questionnaire.
After completing the first round of treatments, all subjects had 2 weeks off before beginning the second round of treatments. The second round of treatments was identical to the first round, other than each subject receiving the other form of CHO-loading drink. During the second round of treatments, each subject was encouraged to eat similarly to their recorded food logs from the first treatment.
Both tests were completed in late November and early December of 2009. During the first testing procedure, the temperature outside was 44°F with 85% humidity, and the wind speed was 0 mph. During the second testing procedure, the temperature was 52°F with 74% humidity, and wind speed was 4 mph. Treatments were counterbalanced, and the 10k was on a competitive track.
The statistical analyses were performed using SPSS 19 (SPSS, Inc., Chicago, IL, USA). A paired t-test was used to compare 10k times in seconds. An alpha of 0.05 was used for significance testing.
Group and individual results are shown in Table 2. There was obviously no statistical difference (t(5) = 0.232, p = 0.83) between Omega 3 Chia loading (mean 10k time = 37 minutes 49 seconds) and CHO loading (mean = 37 minutes 43 seconds).
Participants' reported intakes in food logs were compared between the 2 protocols, and no large (>500 cals) differences were noted. The prerun and postrun questionnaires suggested that 3 of the most highly trained endurance athletes (V̇O2max 78.5-84.2 ml·kg−1·min−1) reported subjective differences between the 2 treatments. One of the half-marathon runners (V̇O2max = 84.2 ml·kg−1·min−1) noted that during the 1-hour run at 65% of their V̇O2max, they had to run faster (ca. 15 s·mile−1) to keep their HR at 65% of their V̇O2 max while on Omega 3 Chia loading treatment. A 1,500-m runner (V̇O2max = 79 ml·kg−1·min−1) stated in the postrun questionnaire that during the Gatorade loading that “he felt worse on the treadmill” and that during the Omega 3 Chia Loading that his “heart rate was lower on the treadmill” in relation to his speed. A half-marathon runner (V̇O2max = 78.5 ml·kg−1·min−1) stated on his postrun questionnaire that “Chia seeds helped me. Felt more energized when I took it. Ran a lot slower on Gatorade (more than I expected). Also, (Gatorade) had too much sugar in it, so it started getting difficult to drink in the afternoon/evening, especially when keeping a regular eating schedule.”
Although 2 of the 3 runners ran slightly faster for their timed 10k with the Gatorade treatment, both of those runners had to run at a faster pace during the first hour of their run to stay within ± 5 b·min−1of their prescribed HR. Keeping HR at 65% of their V̇O2max was the constant, so speed was a variable that was adjusted to keep their HR within their zone. A half-marathon runner (V̇O2max = 78.5 ml·kg−1·min−1), ran faster with the Omega 3 Chia seed loading by 1 minutes 31 seconds, the largest difference between treatments. The only marathon runner of the group (V̇O2max = 47.8 ml·kg−1·min−1) almost broke his 10k personal record (2 seconds slower) with the Omega 3 Chia loading treatment.
All participants reported that both treatments were a lot of calories to drink in a day. One participant noted digestion issues or a little cramping for both treatments. Two subjects reported that they were hungrier while drinking the Omega 3 Chia seed drink.
There was no statistical difference between Greens Plus Omega 3 Chia loading (mean = 37 minutes 49 seconds) and CHO loading (mean = 37 minutes 43 seconds) in timed 10k performance after an hour run at ∼65% of their V̇O2max. This study is the first study to show that a CHO-loading scheme can be manipulated to add in Omega 3 Chia seeds and lead to performances that are statistically similar to CHO loading alone.
The literature has shown that with a high-fat diet, there is a significant increase in fat oxidation during exercise and thus a reduced CHO usage (3-5,8,10,13). The adaptation to a high-fat diet leads to measurable changes in the capacity to store (in muscle), recruit, transport, and use fat for oxidation (7,9,11). There are also literature data to show that there are many techniques of CHO loading and that 8 g·kg−1·d−1 should be consumed to enhance performance (1,15,16). There are no scientific studies that combine a CHO and fat loading strategy.
Sherman et al. (16) reported that “muscle glycogen can be elevated to high levels with a moderate exercise-diet regimen (50% CHO).” It was speculated that 50% CHO could elevate muscle glycogen with a balanced approach to CHO loading that included Omega 3 fats and proper amino acids would prove to be a better performance enhancer than a traditional CHO-loading model that is frequently used by endurance athletes today. However, no advantage was seen from the Omega 3 Chia seed-CHO approach.
Omega 3 Chia loading with additional CHO appears to be an option for CHO loading for endurance events lasting >90 minutes. This approach would allow athletes to decrease their dietary intake of sugar while increasing their intake of healthy Omega 3 fatty acids. A simple scheme that can be used to apply this to a race can be found in Table 3. This dietary approach yielded results similar to traditional all-CHO loading.
We thank Orange Peel Enterprises for supplying the Greens Plus Omega 3 Chia seeds for this study. The results of this study do not constitute endorsement of Greens Plus Omega 3 Chia seeds by the authors or National Strength and Conditioning Association.
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