Doctor's Orders: Don't Forget D!
When it comes to building lean muscle, the supplements that come to mind are ones such as whey protein, creatine, and beta-alanine. Few people consider vitamin D on that list. But you should.
Vitamin D is far more important than just a bone builder. Numerous research studies show that supplementing with vitamin D may raise testosterone levels. Plus, it can aid fat loss, enhance mood, and even support normal, healthy immunity.
There are actually two forms of vitamin D: vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol). D3 is the more potent form, so be sure to stick with that when supplementing.
One study from Creighton University reported that D3 supplements were about 90% more potent at raising levels of 25-hydroxyvitamin D—the storage form of vitamin D in the body—than vitamin D2. It also increased stored levels of the vitamin three times more than D2 did.
Take 4,000-to-6,000 IU of vitamin D in two divided doses with your calcium.
Remember that every rest day should be an active rest day. Rest days are for recovery; they're not an excuse to be lazy. Get out and hit 15-30 minutes of HIIT cardio today, or perform 30-60 minutes of your favorite activity: hiking, biking, walking, playing a sport, etc.