The known benefits are to the cardiovascular system. Because the fundamental challenge of aerobic activity is to deliver more oxygen at a faster rate to your muscles and various organ systems, your body adapts: the chambers of your heart will grow stronger and be able to pump more blood; in the blood, the number of your red blood cells and the volume of your plasma will increase; out at the margins, the small arteries and capillaries in your muscles and skin (where oxygen is being delivered to fuel your activity) will expand, and in those vessels the proportion of so-called good cholesterol (HDL) to bad cholesterol (LDL) will improve.

Beyond the cardiovascular system, aerobic exercise stimulates muscle cells to grow (or hypertrophy) and increase their numbers of mitochondria, the “powerhouses” of cells, where oxygen is burned for energy production. Those muscles will also improve their ability to store carbohydrates and burn fat.

The bones of your skeletal system, which act as the anchor to those muscles, will grow larger and denser when we are young and will repair themselves more effectively when we’re older.

In terms of metabolic effects, aerobic exercise improves your body's ability to use sugar, lowers levels of inflammation and reduces visceral fat (the fat around your organs).

It has many effects too on your endocrine system, beneficially altering your body’s levels of testosterone, oestrogen, cortisol, and growth hormone.

Provided you don’t overdo it, it is also good for your immune system, enhancing its ability to protect you from certain infectious diseases. And finally, sprint interval training will increase blood flow to the brain and stimulates brain cell growth, maintenance, and function which can improve your cognition and mood.