Doctor's Orders: Get Salty
Many people follow a low-sodium diet all the time for fear of their cardiovascular health, water retention, or both. But that can actually work against you. Sodium is one of the most critical elements in the body. While it's true that a small percentage of the population is sodium-sensitive, this likely does not pertain to the healthy person who trains regularly. In fact, all that training causes you to lose more sodium than the average Joe or Jane. Plus, sodium is essential for muscle function and critical for creatine uptake.
If you think that constantly eating very low sodium will keep your body fluid levels low so that you look more ripped, you're wrong. Your body needs to maintain certain levels of water. So, even if you eat miniscule amounts of sodium, your body will adjust to those levels of sodium and will hold as much fluid as if you were eating twice that much sodium. The same goes for eating a higher sodium diet. Even if you consumed more than 4,000 mg of sodium every day, you would not hold water. Yes, you may hold more water temporarily for a few days, but then your body adjusts to the sodium levels and you retain the amount of fluid your body needs.
Your best bet is to keep sodium levels around 3,000-4,000 mg per day. That way your performance and muscle growth won't be limited, and when the time does come to peak for a competition or a photo shoot, dropping water will be easier when you do cut sodium. For those interested in learning how to use sodium and water intake to peak for a competition or photo shoot, read my article 7 Scientific Steps to a Camera-Ready Body.
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.