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<\/div>\n<\/figure>\nWatching an athlete at their peak<\/a> is thrilling.\u00a0Fulfilling one\u2019s own athletic potential, not so much. Getting fit is hard and painful\u00a0\u2013 or\u00a0so we assume.<\/p>\n But that isn\u2019t necessarily the case. In fact, research shows that anyone just starting to exercise more than they are used to\u00a0will see improvements surprisingly quickly, regardless of the workout they choose. Better yet is the discovery that there are ways to speed\u00a0up the fitness journey.<\/p>\n The key to improving fitness is, in essence, simple. You need to exceed your \u201chabitual load\u201d, which is a fancy way of saying doing more activity than you are accustomed to. This\u00a0will stress your body and force it to adapt.<\/p>\n When it comes to starting cardio exercise<\/a> as\u00a0a\u00a0beginner, \u201cone of the first things that happens is you get more blood volume\u201d, says\u00a0Abbi Lane<\/a> at the University of Michigan. Within 24 hours of working out, this increases by up to 12\u00a0per cent<\/a> due to water retention, which increases the amount of blood plasma, boosting the amount of oxygen that can be supplied to the muscles. After two\u00a0weeks of training, peak blood volume is normally reached, which is about 15 to 20 per cent higher in athletes than in sedentary individuals<\/a>.<\/p>\n Energy-producing structures within our cells called mitochondria become more numerous and efficient around this\u2026<\/p>\n<\/p><\/div>\n