Variable Weight (often shortened to VWT), is the freediving discipline that involves descending with weights and ascending without weights by pulling on the rope or finning, may not be a competition discipline anymore, but it can still be useful for your own training and for fun diving. Whether it is used in training for new personal bests or creating more bottom time when fun diving, VWT can be an excellent tool, as long as it is performed safely. Check out the benefits, risks, and safety tips of training VWT below.
Training for Personal Bests
If you are training free immersion (FIM) or constant weight (CWT) and want to acclimatize yourself to a specific depth before attempting it, VWT can be very helpful. You can use it to go 1 or 2m (3 or 6ft) deeper than your personal best (not more than that), check your equalization, and how much pressure you feel, all without a high amount of CO2 in your blood from the descent. Then, when you are ready, you can attempt FIM or CWT with the confidence that you have already been to that depth without adaptation issues.
Check Your Internal Flexibility and Equalization
Our bodies react to pressure, and when the pressure on our bodies is so great that our lungs shrink to their smallest size, it is our diaphragm’s job to be flexible enough to fill the empty space. If our chest is not flexible enough, it can feel like an elephant is slowly stepping on our chest, and Frenzel equalization will start to fail. When we train VWT and go to depths deeper than what we are used to, we can focus more on equalization and pressure rather than contractions, finning, or pulling technique. This gives us the opportunity to know whether we need to stretch more and improve on our internal flexibility.
Allows You to Dive Deep With a Mask
After certain depths, many freedivers make the switch from masks to nose clips, for comfort and efficiency; this takes away the view of the bottom you could be having. With VWT, you can keep the mask on and enjoy the view. This is especially important if you are fun diving a deep reef or a deep shipwreck and want more bottom time. VWT is excellent for giving you that extra time and allowing you to explore deeper depths.
A Training Alternative For Thick Wetsuits and Strong Currents
Those of us who train in colder temperatures know the annoyance of diving in thicker wetsuits. It becomes harder to go deeper as buoyancy changes so much. This also applies to diving in strong current, when it is too much trouble fighting against the current to work on depth. VWT helps with both of these situations since the struggle of descending is eliminated, as the bottom weight is doing all of the work. Thicker wetsuits will also help with the ascent as they are much more positively buoyant.
VWT is virtually effortless. Less finning and less pulling means that you can focus on relaxation and mastering equalization, which is difficult to focus on when other factors are present. VWT can be a much-needed break from your typical training routine, and being able to do it with a mask means also enjoying some scenery on the way down.
If done improperly, VWT can easily become dangerous, which is why it is important to learn from a freediving professional and only practice it on your own (with a buddy, of course) when you are experienced enough. Some of the risks include:
- Entanglement from the drifting line
- Risk of decompression sickness (DCS) due to long hangs at depth
- Mask squeeze from not equalizing the mask often enough
- Middle ear squeeze or perforated/ruptured eardrum if there is an equalization issue and you do not let go of the rope
- Trachea squeeze from looking up instead of tucking your chin in
- Lung squeeze from going to depths that are too deep, too quickly, and not being internally flexible enough
- Always know the topography underneath you and make sure there are no scuba divers below you
- Always wear a safety lanyard
- Remove your weight belt; you should never perform VWT with any weights on your body
- Have some slack at the end of the line, at least 5m (16ft) between you and the bottom weight; this will protect you from crashing into the bottom in the case that the bottom weight unexpectedly hits the sea floor
Professionals perform VWT with a weighted sled, but recreational VWT can be performed with a heavier bottom weight or a bag filled with sand. This does not mean that anyone can train VWT; remember that this discipline can be very dangerous if not performed correctly, which means that you should not train VWT unless you are an experienced freediver who is very familiar with correct safety procedures and proper setting up of a VWT dive. Otherwise, only perform VWT dives with a certified freediving instructor or coach. This will ensure a safe and stress-free environment, which will allow you to enjoy this almost effortless discipline to the fullest!