A recently published article in Bioscience, Biotechnology and Biochemistry (Kawabata, 2014) suggests that a daily dose of 3.6g of fish oil can improve exercise efficiency.
In a double-blind study, the group of healthy male subjects, supplemented with EPA-rich fish oil, experienced a decrease in oxygen uptake needed for sub-maximal exercise. They also perceived the exercise as being easier.
This points to an increase in exercise economy, which is linked to an increase in exercise endurance.
A sachet of KetoactiveMind contains 3.5g of high quality fish oil rich in EPA and DHA in a tasty shot.
Reference: Fuminori Kawabata, Mitsuo Neya, Kei Hamazaki, Yuya Watanabe, Satoru Kobayashi & Tomoko Tsuji (2014): Supplementation with eicosapentaenoic acid-rich fish oil improves exercise economy and reduces perceived exertion during submaximal steady-state exercise in normal healthy untrained men, Bioscience, Biotechnology, and Biochemistry, DOI: 10.1080/09168451.2014.946392
Full text via this link: http://www.tandfonline.com/doi/full/10.1080/.VBnyy0u4nlI