Katie Morell, for example, recently gave tips on the American Express OPEN Forum blog. Some, like "have a plan" and stick to it, are probably familiar to you and not terribly helpful, but a few of the tips she relays from personal trainer Don Miguel, bear repeating. Morell writes:

  • Keep water on hand. According to Miguel, most people have trouble differentiating thirst from hunger. So keep a full water bottle within reach and take a swig every time you get the urge—it can help curb snacking cravings.
  • Eat with intention. It's easy to reach for the sweets or savories, but try keeping more healthy treats around such as nuts, fruits and vegetables.
  • Breathe. Stress can lead to overeating and an increase in blood pressure. Miguel says it's vital to take 30 seconds and focus on your breathing. "A mere 30 seconds may seem like infinity to stop what you are doing at your desk, but it can relax your shoulders and decrease your stress level," he says. Breathe deeply through your nose and out your mouth, Miguel advises. And do it as often as possible.

Miguel and Morell aren't the only ones with tips to help entrepreneurs. Freelance Switch also had tips and reminders recently, including:

  • Ergonomics. Making sure you are comfortable and supported while you spend hours in front of the computer can make a difference—especially when your other option is to fork over money for a weekly massage or worse, wait until the pain is unbearable and end up in bed. 
  • Health Insurance. Depending on where you live, you may or may not have health insurance coverage. It would be a good idea to look into a policy for a self-employed person. You don't want to not go see a doctor when you really need to, which would only exacerbate the problem. Whether it's stress or carpal tunnel syndrome, access to a doctor is important and could make a huge impact on your life. Staying healthy might not be your top priority…but it shouldn't be something you overlook.

What tips and tricks do you have to keep (relatively) in shape while starting up a business?