DevonDiver
N/A
From my experience (also an instructor), John has probably hit the nail on the head. Inappropriate heavy-weighting, incorrect placement of weight around the waist/body and adopting an unnatural position on the knees are three common factors that cause instability in trainee divers. These factors are exasperated when instructors deliberately over-weight students to keep them 'solid' on the bottom whilst insisting on 'from-the-knees' skills practice - it's a 'cheat' that makes the instructors job supposedly easier, at the expense of student's learning proper trim, buoyancy and stability at the outset.
Over-weighting - if you are over-weighted, it is particularly hard to remain vertical. Any variance in body position from 'true' vertical will obviously begin causing a level effect and start pulling you to that side. Over-weighting has other negative effects, such as necessitating a surplus of air in the BCD - which then causes a much greater impact from air compression and expansion as relatively smaller ascents or descents take place in the water. The symptoms of which are students having to constantly add or remove air from their BCD - and the feeling that they are continually over-compensating with their buoyancy for minor depth changes. Solution - conduct repeated weight checks to learn your optimal maximum weight. Reference - Perfect Scuba Weighting article.
Weighting Placement - The location of weighting is important, especially in relation to stability. If using a weight belt, it can slide around the waist and cause you to pull in that direction. Ensure the weight belt is secure and that weights are intelligently dispersed around the belt to prevent an over-tendency in any given direction. Weight-integrated BCDs can also cause problems in this respect, as they hold weights on the front of the torso, further away from the body. Again, both of these problems are particularly significant if trying to maintain an unnatural kneeling position. Solution - Ensure weights are properly dispersed on the weight belt. Ensure the weight belt hasn't rotated around your torso. Reference - Trim and Position article.
Trim and Position - it is very unnatural for a scuba diver to be in a kneeling position. When instructors insist on a kneeling position for skills practice it is because they see it as a quick-fix for class control. However, kneeling down deprives students of developing proper trim and buoyancy at an early stage in the learning process - which has subsequent negative impacts in their long-term development. Get horizontal, into a 'fin pivot' (tips of fins in contact only with the floor) or full horizontal hover and the impact of weight misalignment will be less noticeable. Solution - ​Get horizontal, into a 'fin pivot' (tips of fins in contact only with the floor) or full horizontal hover when you are static on the bottom practicing skills. Reference - Teaching Horizontally article.
Also bear in mind that as a very novice/learning diver, being underwater is a new experience. It does take some time to adjust to the new sensations. You are also quite highly task-loaded, so may feel more stress and frustration than you expected. Rest assured that comfort and relaxation does come in time - especially as experience increases and you learn to relax, stop 'fighting' the water and make beneficial tweaks to your positioning, weighting, buoyancy etc. That said, the issues listed above can be addresses to fast-track your progress into a more comfortable situation...
A few people in the thread have made comments that include "...your instructor will", or "...your instructor should". If your instructor has you heavily weighted and performing all of your skills from a kneeling position then they probably "won't", or believe they probably "shouldn't" decrease your weighting or get your knees up off the floor. Many instructors were initially taught to over-weight and training students from kneeling - this is their instructional philosophy and they may reject other methods - despite PADI and other agencies now extolling the virtues of neutral buoyancy (off the knees) training from an early stage. Talk to your instructor about this - but do be aware that they may (in their minds) not agree with the advice being given in this thread.
Over-weighting - if you are over-weighted, it is particularly hard to remain vertical. Any variance in body position from 'true' vertical will obviously begin causing a level effect and start pulling you to that side. Over-weighting has other negative effects, such as necessitating a surplus of air in the BCD - which then causes a much greater impact from air compression and expansion as relatively smaller ascents or descents take place in the water. The symptoms of which are students having to constantly add or remove air from their BCD - and the feeling that they are continually over-compensating with their buoyancy for minor depth changes. Solution - conduct repeated weight checks to learn your optimal maximum weight. Reference - Perfect Scuba Weighting article.
Weighting Placement - The location of weighting is important, especially in relation to stability. If using a weight belt, it can slide around the waist and cause you to pull in that direction. Ensure the weight belt is secure and that weights are intelligently dispersed around the belt to prevent an over-tendency in any given direction. Weight-integrated BCDs can also cause problems in this respect, as they hold weights on the front of the torso, further away from the body. Again, both of these problems are particularly significant if trying to maintain an unnatural kneeling position. Solution - Ensure weights are properly dispersed on the weight belt. Ensure the weight belt hasn't rotated around your torso. Reference - Trim and Position article.
Trim and Position - it is very unnatural for a scuba diver to be in a kneeling position. When instructors insist on a kneeling position for skills practice it is because they see it as a quick-fix for class control. However, kneeling down deprives students of developing proper trim and buoyancy at an early stage in the learning process - which has subsequent negative impacts in their long-term development. Get horizontal, into a 'fin pivot' (tips of fins in contact only with the floor) or full horizontal hover and the impact of weight misalignment will be less noticeable. Solution - ​Get horizontal, into a 'fin pivot' (tips of fins in contact only with the floor) or full horizontal hover when you are static on the bottom practicing skills. Reference - Teaching Horizontally article.
Also bear in mind that as a very novice/learning diver, being underwater is a new experience. It does take some time to adjust to the new sensations. You are also quite highly task-loaded, so may feel more stress and frustration than you expected. Rest assured that comfort and relaxation does come in time - especially as experience increases and you learn to relax, stop 'fighting' the water and make beneficial tweaks to your positioning, weighting, buoyancy etc. That said, the issues listed above can be addresses to fast-track your progress into a more comfortable situation...
A few people in the thread have made comments that include "...your instructor will", or "...your instructor should". If your instructor has you heavily weighted and performing all of your skills from a kneeling position then they probably "won't", or believe they probably "shouldn't" decrease your weighting or get your knees up off the floor. Many instructors were initially taught to over-weight and training students from kneeling - this is their instructional philosophy and they may reject other methods - despite PADI and other agencies now extolling the virtues of neutral buoyancy (off the knees) training from an early stage. Talk to your instructor about this - but do be aware that they may (in their minds) not agree with the advice being given in this thread.