the arm is an extention of your hands- let me explain there is a what called a riders outline -there should be two lines schoulders -hip- heal and elbow through tthe hand to the horses mouth
a horse in the correct position can be spoilt by a sloppy looking rider the riders toes should be above the leve of the heel, with a relaxed ankle, its would be easy for the rider to push the toes upwards or pointing straight rather than pushing down tend to make the lower leg go forwardsand will create problems later on when learning to leg yield etc
once the rider has the corect position then its head up, or chin up and look forwards dont have the habit of looking down as this will defat the objective
and wont be looking where your going if you dont look then your hands cant follow through and neither can the horse
if ones tilting or leaning into the head then one is using the horses head/ bridle area to support there body weight
so one must learn to have balance - and work with an indendant seat of legs and hand
position is the key------ if ones not sitting centerally on the horse then ones not distributing there body weight evenly thus will hang onto the horses head
and grip for dear life then the horse complains as its uncomfy for them
in one instence your asking thehorse to go but are confusing him with the support of your body weight into his head and see intrepretates that as stop/go
so a confused signal to the horse
ask if you can go on the lunge and do some work without stirrups
as in walk and trot and mounted standing still like scissors, round the world,
pulling your legs into frog position or racing position whatever you want to call it
as most problems with tightness is lack of balance so you tend to tense up as to grip more so ,which effects your riding
so try doing things with out stirrups as this will help you learn to have an independant seat plus balance plus confidence plus
once you done the simpler exercises then you can move upto to working with out stirrups over ground poles an trot poles with out the lunge line attached
so start off with very simple exercises, like getting on getting off its all helps with relaxation, round the world clockwise and anti clockwise, half mounts, ie mount up lean right over said horse with both feet on one side then pull yoursellf up into sitting position thus do it both sides builds up your strenght to, also mount from the opposite side
another you can try - simple ones - if you have someone on the lunge ie a trianer or helper, then reach with right hand and touch left toe- dont pull foot upwards just move toes upwards and bend right down and touch your toe then repeat on opposite side
reach left hand touch horses right ear and visa versa
hold out one arm out stretched - then change hands to the other side
feeling brave hold out both arms and star burst - ie legs of only bum is holding you into the saddle and count to ten before you put your hands and legs back
repeat 4 times if braver
another simple exercise- arms out legs out and twist your body left then right
not the hips the body your turso - loo k left and right as you do it
legs arms back on the
all these simple exercises gain confindence and sticky bum glue
and help you to relax whe riding a horse but to begin with you do need someone with a bit of savvy so that they can control your horse for you on the lunge
play with your horse like this and it will make you less tense and will build a bond with him of trust
work on your seat area and this will help with your arms as its not so much as your arms but your balance and position
set yourself up correctly by altering your sitrrups to the correct lenght which is explain on my helpful links pages here
http://chronofhorse.com/forum/showthread.php?t=178116
also read all links as its all relevent on page 1 and read page 1