The idea that microbes induce disease has steered medical research toward the discovery of antibacterial products for the prevention and treatment of microbial infections. The twentieth century saw increasing dependency on antimicrobials as mainline therapy accentuating the notion that bacterial interactions with humans were to be avoided or desirably controlled. The last two decades, though, have seen a refocusing of thinking and research effort directed towards elucidating the critical inter-relationships between the gut microbiome and its host that control health/wellness or disease. This research has redefined the interactions between gut microbes and vertebrates, now recognizing that the microbial active cohort and its mammalian host have shared co-evolutionary metabolic interactions that span millennia. Microbial interactions in the gastrointestinal tract provide the necessary cues for the development of regulated pro- and anti-inflammatory signals that promotes immunological tolerance, metabolic regulation and other factors which may then control local and extra-intestinal inflammation. Pharmacobiotics, using nutritional and functional food additives to regulate the gut microbiome, will be an exciting growth area of therapeutics, developing alongside an increased scientific understanding of gut-microbiome symbiosis in health and disease.

Introduction: For older adults regular participation in physical activity has the potential to improve their health and wellbeing. Nonetheless, research indicates that up to 50 percent of older adults are insuffi ciently active to realise health benefi ts and knowledge of what promotes an older person’s interest in regular physical activity is limited. The aim of this study was to better understand the complex interactions of factors that motivate older people to take up and maintain regular physical activity. Methods: A short survey of activity levels, perceptions of physical activity and social support for being active were completed by 223 participants aged 65 years and older (M = 81 years, SD = 7 years). A series of semi structured interviews exploring perceptions, motivations and barriers around physical activity were also conducted. Inductive thematic analysis was employed to identify common themes and experiences from interview transcripts. Results: Participants engaged in higher levels of physical activity than those previously reported in the literature. Interviews revealed that participation in physical activity was prompted by the need for engagement with others, support from enthusiastic instructors/staff and a sense of competition/task achievement. Discussion: The need to be engaged in and challenged by activities does not decline with advancing age and programs to support older people to stay active need to recognise these factors.

One enjoyable aspect of our A-Z series is that an issue often comprises a real assortment, such as occurs here. We have: citrulline, a non-essential amino acid; coenzyme Q10, a coenzyme that is part of the total antioxidant system; colostrum, the initial milk produced by mammals after giving birth, with bovine colostrum being a popular supplement among athletes because of its reported immune benefits; this is followed by conjugated linoleic acid, a series of structural and geometric isomers of linoleic acid which may play a role in optimising body composition; and, finally, copper, a mineral with multifunctional uses that may require monitoring in athletes at risk. We are grateful to our invited reviewers for their excellent contributions giving impartial advice on the value of these individual nutrients and supplements. They are establishing that, for some, performance evidence is limited or simply does not yet exist.