Surfing Waves

I have a 6'2" board, about 35L volume. I workout 6 days a week, but still don't have the greatest arm strength. I am a 15 y/o female. I am 5'3", about 110 lbs. Is this a decent board for duckdiving? I know it requires a lot of practice. (Currently am using other methods to get out the back, but struggling.) Does anyone have a certain spot where they grab the rails to sink the board? Sinking the board is my main issue right now.

Any duckdiving tips would be great

Thanks in advance!

At your weight, duckdiving willl always be a challenge, but not impossible. Certainly you'll need to learn to do it well, which is all about commitment and timing... just like anything else in surfing.

When I duckdive, my hands are on the rails and a little bit further forward than they would be for the pop up - almost at my shoulders. So, like a press-up, but with one foot on the tail pad, then dive forward with your head, and push your other foot up as hight as it will go. As much of you out the water as you can, then follow the surf board down.
Then pivot the board down, along and then up around your foot on the tailpad in a kinda scooping motion.

Takes a lot of practise but well worth the effort.

Just like your rushed to go down to a smaller board, do NOT rush to duckdive. Take it in baby steps. Technique is more important than Power. Do not try to duckdive deep like 3 feet. Forget about even 1 foot deep. Just lay on your board when there's no waves. Scoot your head up to the nose and with both hands and back foot's ball on the tail pad's kick, push down. But only 1 inch. Yes, one inch. See how long you can hold without getting wiggle side to side. Chin stays above the surface and elbows will be bent. After you got that down, then increase another inch and so on. Soon your chin will be touching the water with your arm extending full straight down. There's a few more steps, but get holding the board down first.