A day in the life of a Real Estate Associate can be exhausting and while you may get home and just want to kick your feet up on the coffee table at the end of it know that it did have a benefit BUT it was not EXERCISE. What wore you out was Physical Activity and not EXERCISE. The latter is comprised of an intentional physical activity which is purposeful, planned, structured and most important repetitive. Both maintain your fitness level while exercise is used to improve it.
Whatever your level of fitness is there's a cumulative effect of work and exercise which gets you to that level. To go beyond you'll need to add to the normal routine. As I age the tendency is to perform these activities in a more efficient manner. Not necessarily more weight or more repetition but higher intensity. Age brings some limitation although a lot of it is in our minds and not the body. To those who use weights or machines in their workout try slowing down your reps? Three seconds on the contraction and 7 to 10 seconds for the negative motion. It takes a lot more effort and concentration to match the normal amount of repetitions you used to do although it's a great way to introduce new muscle fiber to the party. Another addition to this can be a simple hard squeeze at the point of full muscle contraction, hold it for 1 to 2 seconds then continue, sounds easy but it isn't. Always have a spotter when experimenting with something new!
It's all about HEART HEALTH and not so much how we attain it. In my prime I had a resting pulse of 43 BPM. Two years ago I was at 78 and today it's 61. I want to be in the mid 50's and believe I can get there which isn't bad for a sexagenarian. Addressing the runners and swimmers or those more aerobically inclined take a look at your workout and find points along your route where an incline may exist and use it to your advantage by sprinting that segment. Swimmers may want to sprint 50 yards at a time in one minute intervals. If you can get through twenty of these that's fantastic. I hope you're grasping the idea. It's not how much time you spend doing something it's are you getting the benefit from your time spent.
Small form changes will bring big gains to your overall fitness.