Does fish oil improve muscle strength?

The answer seems to be a cautious 'yes', when combined with moderate exercise. But at the moment, it seems to depend on how old you are, your gender, and what kind of fish oil you are supplementing your diet with.

Sarcopenia is a naturally occurring condition that affects people as they get older. It results in muscle wastage, where muscle size is reduced by 0.5-2% per year, and it can result in frailty and reluctance to engage in all kinds of activities.  Data from the USA shows that 25% of people aged 50-70 have sarcopenia, and this rises to over 50% for those over 80. One way muscle function can be maintained is through exercise.  However, though for young people (18-35) exercise increases muscle mass, as we age our body becomes less able to increase muscle mass through exercise alone.

A recent trial by University of Aberdeen scientists presented last week at the British Science Festival examined if the consumption of fish oil combined with weight training exercises could help protect the elderly against this muscle wasting. The results demonstrated that women aged over 65 who received omega-3 fatty acids gained almost twice as much muscle strength following exercise than those taking olive oil (the placebo group). After 12 weeks of resistance exercise training those taking fish oil improved muscle strength by 20% compared to an 11% increase in the placebo group. These results were so encouraging that a bigger study involving both men and women is now under way.

The study authors venture that the inflammation response is key in explaining the effects of the fish oil. They believe that the low-level inflammation that older people tend to have interferes with the the muscles’ ability to increase strength and mass. The anti-inflammatory properties of fish oil may reduce this inflammation, and help to reduce this interference. They also believe that the composition of the oil may make a difference, as not all commercially available fish oils contain the amounts of EHA and DHA in the fish oil provided to study participants. The study authors recommended supplementing diet with fish oils containing high proportions of these two fatty acids.

Given that endurance athletes - especially runners - can show all kinds of signs of inflammation after long training sessions, I wonder if it is worthwhile thinking about supplementing with fish oil to help reduce this inflammation interfering with muscle repair? I haven't looked to see if this has been done, but it would be an interesting study, and the kind of thing that athletes can do with little risk of harm.