As a dad who had his first at age of 40 I can say it ' s fucking hard . You do have the advantage of being in a better financial and life position , but it takes a lot out of you mentally and personally . It ' s much harder to balance everything as your value on time and things you have in your life is higher than when you are you and don ' t give so much of a fuck . That said , having kids young can have a big impact on life choices and directions . I wouldn ' t be in my chosen career and earning what I do if I had kids young . I dunno , life would be different . Physically ? Yeah , it ' s a lot harder , and I have to consciously work on it and maintain my fitness in order to keep up and do stuff my daughter would like me to do like run in park , swim at beach , cycle etc . It ' s so important I reckon . It can be a motivator as well , you feel you owe it to your kids to be as health and active as you can in order to live and do for as long as you can .