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Long-chain omega-3 polyunsaturated fatty acid (LC n -3 PUFA) supplements, rich in eicosapentaenoic acid and/or docosahexaenoic acid, are increasingly being recommended within athletic institutions. However, the wide range of doses, durations and study designs implemented across trials makes it difficult to provide clear recommendations. The importance of study design characteristics in LC n -3 PUFA trials has been detailed in cardiovascular disease research, and these considerations may guide LC n -3 PUFA study design in healthy cohorts. This systematic review examined the quality of studies and study design considerations used in evaluating the evidence for LC n -3 PUFA improving performance in physically trained adults. SCOPUS, PubMed and Web of Science electronic databases were searched to identify studies that supplemented LC n -3 PUFA in physically trained participants. Forty-six (n = 46) studies met inclusion. Most studies used a randomised control design. Risk of bias, assessed using the design-appropriate Cochrane Collaboration tool, revealed that studies had a predominant judgment of 'some concerns', 'high risk' or 'moderate risk' in randomised controlled, randomised crossover or non-randomised studies, respectively. A custom five-point quality assessment scale demonstrated that no study satisfied all recommendations for LC n -3 PUFA study design. This review has highlighted that the disparate range of study designs is likely contributing to the inconclusive state of outcomes pertaining to LC n -3 PUFA as a potential ergogenic aid. Further research must adequately account for the specific LC n -3 PUFA study design considerations, underpinned by a clear hypothesis, to achieve evidence-based dose, duration and composition recommendations for physically trained individuals. [ABSTRACT FROM AUTHOR]

Aims: Supplementing animal diets with high-dose fish oil, rich in long chain omega-3 (ω-3) docosahexaenoic acid (DHA), enhances cardiac contractile efficiency and attenuates dysfunction, attributable to ischaemia. However, it remains unclear whether smaller doses, equivalent to what is achievable via regular fish consumption in the human diet, offer similar protection. Methods: Male Sprague–Dawley (12−15w) rats were fed isoenergetic diets (ad libitum) containing 10% fat by weight (22% energy) for 4–5w. Control diet (CON) contained 5.5% beef tallow; 2.5% ω-6 sunflower seed oil; 2% olive oil. Fish oil diets included high-DHA tuna oil exchanged for olive oil to provide 0.32% (FO1; human equivalent EPA + DHA 570 mg/d) or 1.25% (FO2; equivalent EPA + DHA 2.3 g/d) wt/wt dose of fish oil. Anaesthetised rats (pentobarbital: 60 mg/kg i.p.) were subjected to 45 min coronary artery occlusion then reperfusion in vivo as a whole animal model of regional myocardial ischaemia, with left ventricular haemodynamic function measured by conductance catheter. Results: Ischaemia-induced reductions in rate pressure product recovered faster in the FO2 group and post-ischaemic left ventricular pressure–volume loop integrity (shifted downwards and right in CON) was partially protected in both fish oil groups. Conclusion: Ischaemia-induced contractile dysfunction in rats is limited from fish oil doses equivalent to regular consumption of fish in the human diet. These observations highlight plausible and clinically relevant physiological changes that rationalise nutritional conditioning of the heart with DHA for on-going cardioprotection. [ABSTRACT FROM AUTHOR]

This pilot study sought to determine whether a low, supplemental intake of fish oil would raise the Omega‐3 Index (O3I) and improve physical fitness in healthy older adults. Participants (70 ± 3 years) were randomised to 2 g/day of either sunola oil (control; n = 8, 62.5% female) (1700 mg/day oleic acid) or docosahexaenoic acid (DHA)‐rich fish oil (FO; n = 9, 55.6% female) [delivering 560 mg/day DHA and 140 mg/day eicosapentaenoic acid (EPA)] for 16 weeks. The O3I, physical fitness, 400 m walking speed and heart rate (HR) parameters were assessed. O3I was increased after FO (mean ± SD, control: pre 6.1 ± 0.8, post 5.9 ± 0.6; FO: pre 6.0 ± 0.6, post 8.3 ± 1.2 p < 0.05). Mean lowest overnight HR (control: pre 58 ± 6, post 58 ± 6; FO: pre 55 ± 6, post 52 ± 6 bpm, p < 0.05) and mean HR during fast walking (control: pre 120 ± 6, post 124 ± 7; FO: pre 122 ± 6, post 115 ± 6 bpm, p < 0.01) were reduced in the FO group without a change in walking speed (control: pre 1.55 ± 0.17, post 1.58 ± 0.20; FO: pre 1.59 ± 0.15, post 1.59 ± 0.18 m/s), HR variability or physical fitness. The changes in lowest resting HR and fast walking HR significantly correlated (inversely) with the changes in O3I. This nutritional approach of providing dietary achievable DHA offers a potential opportunity to reduce cardiovascular strain during physical activity in the older adult. [ABSTRACT FROM AUTHOR]

Dietary fish oil modifies skeletal muscle membrane fatty acid composition and oxygen efficiency similar to changes in the myocardium. Oxygen efficiency is a key determinant of sustained force in mammalian skeletal muscle. Therefore, in the present study, we tested the effects of a fish-oil diet on skeletal muscle fatigue under the stress of contraction using the rat in vivo autologous perfused hindlimb model. For 8 weeks, male Wistar rats were fed a diet rich in saturated fat (SF), a diet rich in n-6 PUFA or a diet rich in long-chain (LC) n-3 PUFA DHA derived from fish oil. In anaesthetised, mechanically ventilated rats, with their hindlimbs perfused with arterial blood at a constant flow, the gastrocnemius–plantaris–soleus muscle bundle was stimulated via sciatic nerve (2 Hz, 6–12 V, 0·05 ms) to contract repetitively for 30 min. Rats fed the n-3 PUFA diet developed higher maximum twitch tension than those fed the SF and n-6 PUFA diets (P< 0·05) and sustained twitch tension through more repetitions before the tension declined to 50 % of the maximum twitch tension (P< 0·05). The n-3 PUFA group used less oxygen for tension developed and produced higher venous lactate concentrations with no difference in glycogen utilisation compared with the SF and n-6 PUFA groups. These results further support that incorporation of DHA into skeletal muscle membranes increases the efficiency of oxygen use over a range of contractile force and this is expressed as a higher sustained force and prolonged time to fatigue. [ABSTRACT FROM PUBLISHER]

The article reports on the effect of parallel consulting on the quality of consultations in regional general practice. It is stated that there is no loss in consultation quality, as experienced by the patient, when using the parallel consulting model. The recent rise in the number of Australian medical students, combined with the Federal Government rural bonded scholarship programme, has provided impetus to increasing the delivery of medical training to students.