Exercise does not directly produce increases in muscular strength and size. If performed intensely enough, the stress of exercise stimulates your body to produce an increase in the strength and size of your muscles as an adaptive response.
For your body to produce the increases in muscular strength and size stimulated by your workouts it needs time, along with adequate protein and calories, and quality sleep.
Even if you exercise intensely and stimulate your muscles to grow, and even if you are eating enough quality protein and calories to support recovery and growth, if you don’t give your body enough time off between workouts you will interfere with the process and prevent it from producing all the strength and size gains you worked for.
The more intensely you train, the stronger the stimulus for growth, but also the more stressful it is on your body, and the more quickly you reach a point of diminishing returns as your workout volume and frequency increase. If you work out too long and/or too frequently, you’ll gain less muscle, not more. If you train too long and/or too frequently for long enough, you will eventually become overtrained and start to become smaller and weaker.
Most people need at least one day off between workouts for recovery, regardless of whether you are training your whole body or splitting it up, and should work out no more than three times per week on non-consecutive days. Some people take longer to recover and will get better results only working out twice a week or less frequently (or alternating between upper and lower body workouts, so they’re only directly working individual muscle groups twice weekly on average).
If you train very intensely you can even get good results training as little as once per week. I know many HIT instructors who only work out and train most of their clients once weekly with good results. I only worked out for about twenty minutes once per week while getting ripped for a bodybuilding competition, just to prove it could be done.
However, if you recover fast enough to train more frequently, and don’t mind a little extra time in the gym each week, training as often as your recovery allows will provide faster muscle gain.
I’ve made good progress training once weekly in the past, but I recover fast enough (when I am eating and sleeping well) to train each muscle group twice weekly, so now that I’m working on getting back in contest condition I’m doing exactly that.
This isn’t a blanket recommendation, though. Like most things about exercise, response varies between individuals due to genetics and other factors, and there is no single frequency that is best for everyone. There is a middle ground that will be effective for most people, and makes a good starting point, but what is optimal for each individual varies.
You have to figure it out for yourself by keeping accurate records of your workouts and using them to evaluate your progress, adjust variables, and repeat until you find the frequency that works best for you (or hire me do it for you).
Every time you work out write down everything you do in detail on your chart or in your workout journal, and periodically measure, record, and compare your body weight, composition, and circumference measurements. Evaluate how your body is responding, adjust your workout, re-evaluate a month or two later, and repeat, until you’ve found your optimal frequency.
If you are not gaining strength and size despite training very intensely, and getting adequate rest, the problem may be either too much workout volume, not enough recovery time, or both. Experiment with cutting one of these back at a time, and compare your results.
Keep in mind the longer you have been training the slower you can realistically get bigger and stronger. When you’re starting out you should be able to gain relatively quickly if you are training and eating correctly, but even if you do everything perfectly your progress will slow down more the closer you get to the limits of your genetic potential. You will also recovery and adapt more slowly as you age.
To help you track your workouts and body measurements so you can determine your optimal workout volume and frequency (and save you the time and hassle of putting them all together yourself), I am creating a short ebook on Tracking Progress with several printable workout charts designed for high intensity training, a body data chart for tracking weight, composition, and circumference, a nomogram for estimating body composition from skinfold measurements, and detailed guidelines for all of using them.
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