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[The_Bulldog]

Roe Of Marine Animals Is Best Natural Source Of Omega 3


The roe of hake, lumpsucker and salmon is the best dietary source of Omega 3, according to a study carried out by researchers at the University of Almería (UAL). The scientists analysed the eggs, or roe, of 15 marine animals, and found all of these contained high levels of these fatty acids, which are essential to the human body.

Until now there had been no precise understanding of the nutritional potential of the roe of marine animals, but a team of researchers from the UAL has now shown that this is one of the best natural sources of Omega 3 fatty acids, which are essential for ensuring the correct development of a wide variety of metabolic functions in the human body.

"We have classified these eggs as unequivocal sources of Omega 3, and have proven that this appears at high concentrations in all the species studies", José Luis Guil Guerrero, director of this study and a researcher in the Food Technology Department of the UAL, tells SINC.

The results, published in the European Journal of Lipid Science and Technology, show that Omega 3 fatty acids are present in all fish roe, but especially in the eggs of Atlantic bonito (Sarda sarda), mackerel (Scomber scombrus), squid (Loligo vulgaris), cuttlefish (Sepia sp.), lumpsucker (Cyclopterus lumpus), hake (Merluccius merluccius) and salmon (Salmo salar).

The team studied the fatty acid content in the eggs of 15 marine animals, focusing their research on two types of Omega 3 eicosapentaenoic acids (EPA) and docosahexaenoic acids (DHA). More than 30% of the fatty acids found in these eggs were EPA and DHA.

The conclusions of the study also show that minimal consumption of lumpsucker, hake or salmon roe satisfies the human body's Omega 3 essential fatty acid requirements, because of its levels of EPA y DHA. A lack of these compounds is associated with cardiovascular disease, hypertension, depression, diabetes, poor development of the nervous and reproductive systems, and inflammatory diseases, such as Crohn's disease.

"Aside from their nutritional importance, we could also make use of roe to extract its oil, which is rich in PUFAs (polyunsaturated fatty acids) and can be used as a dietary supplement, since it has a higher Omega 3 content than regular oils, for example salmon and tuna oil", explains Guil Guerrero.


Article Date: 12 Dec 2009
Source: Plataforma SINC

[The_Bulldog]

Leucine supplementation and intensive training.


Leucine, isoleucine and valine, the branched-chain amino acids (BCAA), make up about one-third of muscle protein. Of these, leucine has been the most thoroughly investigated because its oxidation rate is higher than that of isoleucine or valine. Leucine also stimulates protein synthesis in muscle and is closely associated with the release of gluconeogenic precursors, such as alanine, from muscle. Significant decreases in plasma or serum levels of leucine occur following aerobic (11 to 33%), anaerobic lactic (5 to 8%) and strength exercise (30%) sessions. In skeletal muscle, there is a decrease in leucine level and a reduction in glycogen stores during exhaustive aerobic exercise. Basal fasting serum leucine levels decrease by 20% during 5 weeks of speed and strength training in power-trained athletes on a daily protein intake of 1.26 g/kg bodyweight. The leucine content of protein is assumed to vary between 5 and 10%. There are suggestions that the current recommended dietary intake of leucine be increased from 14 mg/kg bodyweight/day to a minimum of 45 mg/kg bodyweight/day for sedentary individuals, and more for those participating in intensive training in order to optimise rates of whole body protein synthesis. Consumption of BCAA (30 to 35% leucine) before or during endurance exercise may prevent or decrease the net rate of protein degradation, may improve both mental and physical performance and may have a sparing effect on muscle glycogen degradation and depletion of muscle glycogen stores. However, leucine supplementation (200 mg/kg bodyweight) 50 minutes before anaerobic running exercise had no effect on performance. During 5 weeks of strength and speed training, leucine supplementation of 50 mg/kg bodyweight/day, supplementary to a daily protein intake of 1.26 g/kg bodyweight/day, appeared to prevent the decrease in the serum leucine levels in power-trained athletes. According to 1 study, dietary supplementation of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) 3 g/day to humans undertaking intensive resistance training exercise resulted in an increased deposition of fat-free mass and an accompanying increase in strength. Muscle proteolysis was also decreased with HMB, accompanied by lower plasma levels of enzymes indicating muscle damage and an average 50% decrease in plasma essential amino acid levels. Furthermore, BCAA supplementation (76% leucine) in combination with moderate energy restriction has been shown to induce significant and preferential losses of visceral adipose tissue and to allow maintenance of a high level of performance. Caution must be paid when interpreting the limited number of studies in this area since, in many studies, leucine has been supplemented as part of a mixture of BCAA. Consequently, further research into the effects of leucine supplementation alone is needed.


Department of Biology of Physical Activity, University of Jyväskylä, Finland

[The_Bulldog]

Effects of branched-chain amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise.


BACKGROUND: The aim of this study was to examine the effects of branched-chain amino acid (BCAA) supplementation on serum indicators of muscle damage after prolonged exercise. We hypothesized that BCAA supplementation would reduce the serum activities of intramuscular enzymes associated with muscle damage. METHODS: To test this hypothesis, sixteen male subjects were assigned to one of two groups: the supplemental group (consuming 12 g x d(-1) BCAA for 14 d in addition to their normal diet) or the control group (normal diet only). Baseline serum creatine kinase (CK) and lactate dehydrogenase (LDH), shown to be accurate indicators of muscle damage, were determined during the week before the exercise test. The exercise test was administered on day seven and required the subjects to cycle for 120 min on an ergometer at approximately 70% VO2max. Blood samples were taken prior to and immediately following exercise and at 1 hr, 2 hrs, 3 hrs, 4 hrs, 1 d, 3 d, 5 d and 7 d postexercise. All subjects were required have their diets analyzed daily during the 14 d. RESULTS: Dietary analyses indicated that all subjects consumed the recommended daily intake of BCAA (0.64 g x kg(-1)) in their normal diets. Baseline serum values for CK and LDH were not different between groups in the 7 d prior to the test (p>0.05). However there were significant increases (p<0.05) between the pre-exercise and postexercise values for LDH and CK until 5 d postexercise test. Importantly, the BCAA supplementation significantly reduced this change in LDH from 2hrs to 5 d posttest, and CK from 4 hrs to 5 d post-test (p<0.05). CONCLUSIONS: These results indicate that supplementary BCAA decreased serum concentrations of the intramuscular enzymes CK and LDH following prolonged exercise, even when the recommended intake of BCAA was being consumed. This observation suggests that BCAA supplementation may reduce the muscle damage associated with endurance exercise.


Centre for Human Movement, University of Tasmania, Launceston, Australia.