It is common knowledge that smoking and working out do not go well together. Smoke causes your lungs to feel heavy, and seriously undermines your efforts to workout and stay healthy. With this thinking in mind, many people assume that vaping is a better alternative, and perfectly fine to do after a workout. The problem is that while the vapor in e-cigs is certainly gentler on the lungs, it does nothing about the nicotine, which can be just as detrimental to a good workout as smoke. This is especially true if the e-liquid you are using contains a high nicotine level.
First off, nicotine is a stimulant, which means it is going to make your heart beat much faster than it should be. This is bad while working out because it is going to cause you to burn through your energy far quicker than normal. The same applies for after a workout. If you are vaping after a workout, you are preventing your body from cooling down. You may feel relaxed while vaping, but in reality the nicotine is actually preventing your body from resting.
Nicotine also reduces the level of oxygen in your blood. Your muscles need high levels of oxygen after a workout in order to grow. Therefore, if you are vaping after a workout, you are reducing your gains from that session. What's more, nicotine also negatively affects the cells that produce testosterone, which is also essential for muscle growth. If you are vaping after a workout, you are bottle necking two of the essential ingredients of muscle growth.
You should also keep in mind that while vaping is less irritating to the lungs, it can still cause some heaviness. This really depends on how often you are vaping, but if you are a frequent vaper, then you will notice yourself breathing harder on cardio workouts.
Vaping is an undeniably better alternative to smoking, but should be done cautiously before or after working out. If you have to vape after a good workout, try to wait a good half hour or so, so that your body has enough time to cool down. If you vape the moment you're out the gym door, then again, you are seriously undermining yourself by reducing your gains.