We all know someone that has had cancer. In our family my dad and sister are cancer survivors. And although this disease is very close to all of us we often don't know what to do when it comes to exercise and cancer. Should you exercise or not? Does it help or harm? I'm not an oncologist and so don't take these ramblings as medical advice. But I still keep an eye on the research and stay informed as more information on this topic becomes available. A paper out of the Karolinska Institute in Sweden gives some promise for exercise with cancer. The authors looked at over 100 studies, involving over one million adults and 13 different types of cancer. What they found was that exercisers had better outcomes, related to their cancer, than those who didn't exercise. It appeared that exercise helped prevent the onset of cancer. And it helped the body fight back more effectively against the cancer. So how does this happen? Well it appears there are particular immune cells, cytotoxic T cells, that are positively influenced by the effects of exercise. These immune cells, aka killer T cells, have enhanced function with individuals that exercise. Representation of the role of T cells Source: https://www.thoughtco.com/t-cells-meaning-373354 Researchers have transferred the T cells of mice that exercise, to non-exercising mice, and seen tumour reductions. More specifically it appears that certain metabolites are produced during exercise that play a role. Lactate, in particular, seems to bolster T cell activity. When mice where given sodium L-lactate there was an increase in T cell activity and greater decrease in tumour growth. While this all sounds promising there are a few things to keep in mind: The papers reviewed and cited included adults with cancer. We might expect similar results with children but the...