As we age our bodies don't work the same way they use to. Our metabolism slows down, our taste buds appear and disappear, we start eating more salads, and our hormones slump. Yet, it doesn't have to be like that. You can look good and feel good at any age as long as you put in the work.
Health science provides a basic fundamental of what good dieting and exercise implicates. However, your body does not operate on the same instructions at every age. Seems logical right? Well it's been confirmed - the University of Oklahoma conducted a study on 24 men aged 18 to 22 and 25 men aged 25 to 50. They got them to follow the same weightlifting routine for 8 weeks. Guess what they found? The older group had a harder time recovering from exercise and the younger group had developed muscle memory less than halfway through programming. They also discovered that both groups were able to put on a significant amount of muscle mass.
Since persistence and patience come with age so does struggle and abuse. You cannot get away with knee bowing, elbow flaring, back-arching, half-squatting, heavy pulling reps anymore. And certainly can't do so whenever you please.
So the question being, how do you get an above-average physique according to your age profile? Simple. Adjust when you workout. Here's when and why:
In your 20s:
Around 3pm. This is when you have the MOST amount of energy in the day and allows you the opportunity to develop an appetite for dinner. This is also the best stickler if you are new to training. Also, our lungs function almost 15% more efficiently by this time.
In your 30s:
Early in the morning, around 8am. The dirty thirty is when you've realized that your metabolism has slowed down at least 3% and have a much less active lifestyle than in your 20s. Getting the day started with a great fitness sesh allows for your metabolism to exert unwanted calories and keep burning unwanted calories throughout the rest of the day.
In your 40s:
Same as your 30s but you want to focus on increasing volume and decreasing weight. At this point however, you're wise enough to make your own decisions.
In your 50s:
Surprisingly, late in the evening. This will help you sleep better and help you wake up rested. Also, in the evening, exercise was found to reduce blood pressure by 10-11%.
However, your body and brain function to yourself individually. What works well for person x may not work well for person y - it is important to seek and challenge your body and make an analytic decision on what is best for you.