I can stand up in my dream what does this mean?

In my dreams... I always have pretty normal dreams but the wierd thing is that I can't seem to stand up! Like if I try to sit down in my dream, it's like I sit really skewed like I have one letup on the chair and I can't control it and people in my dream sometimes notice it but it's not out of the norm. But most always when I'm walking I can't stand up I slowly fall to the ground like I my legs don't work right. And if I'm getting chased in my dream like if theirs a robber in my dream they always catch me because I can't run I just fall down and can't get away! So if anyone has a feeling that they think that it means something email me with the subject "DREAM" please! BUT if someone knows the educational or scientific reason or cause of the dream PLEASE email me I would REALLY appreciate it! Please email me with the same subject "DREAM"! Thanks so much for spending your much appreciated time and guidance! If anyone has any comments or suggestions, please feel �free to email me I really would love to hear from you all. My email is Kozik.Kristen@yahoo.com. My name is Sunshine ! Again thank you for your time and concern!<3 <3 <3