Obstacles can be both tangible and intangible as you strive to achieve your goals throughout your life. We like to believe that we know how the future will play out but more often than not it doesn't turn out that way. For some reason we (as humans) often find ways to hold ourselves back from achieving our own goals. It's one reason or another, an event, previous commitment, its raining, ext.. All excuses that our brain will come up with to justify why you haven't achieved your goal yet. The problem with this is that it's those very same excuses are now your obstacles that you've created for yourself. The best piece of advice i can give you is to not listen to your brain. That organ that lives between your ears will tell you to stop, it'll tell you you can't do something, but in reality it's only because it's telling you that. It's not the truth, it doesn't exist as a real tangible barrier. Those obstacles aren't real.. It's simply all in your head! Your body is far more capable of achieving greater accomplishments than your mind wants to allow it. Stop listening and start doing because you can!