Tag Archives: training

Become a better diver with strength training for freediving

How should we train? Is strength training for freediving a good idea? Are bigger muscles better or worse? Should we hit up the gym in the off season?

I have alluded to some of these questions in previous posts and newsletters. In my mind, there is no doubt that a well trained muscle performs better during freediving activities. Unless you are purely interested in statics, strength training will benefit you.

Muscles store both energy and oxygen, and a trained muscle can store more of both. But (there is always a but), it is difficult to load a muscle with oxygen, or rather, the oxygen carrying protein myoglobin. So instead I’ll show you how you can load it with energy, or rather, the phoshate molecule creatine phosphate.

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Free webinar: Training with a MOXY muscle oxygen sensor

The MOXY is a muscle oxygen sensor that can measure the saturation of hemoglobin and myoglobin of for example your quads.

Do you think your apnea walks are effective?

They might be. You can practice apnea walking with an oximeter, but it is hard to know exactly what is going on in the muscles. For some training you don’t need the oxygen in the muscles to drop, and for other training it needs to drop as much as possible.

Now, the guesswork is over.

Using a MOXY muscle oxygen sensor it is possible to measure the oxygen content in the muscles. You can strap the MOXY to your quad, biceps, or any other muscle to gauge the level of oxygen during exercise.

MOXY oxygen monitor.
The MOXY can be used to measure the oxygen levels in your muscles during exercise. Image taken from here

I have tested a set of exercises, including apnea walking, apnea squats, and bicycle interval training using the MOXY and will be sharing my results during a free webinar. The webinar will start at 12 noon CST, Tuesday December 12th, and run until about 12.45. There will be ample time for questions.

Register for the free webinar now!

Hope to see you there.

A practical guide to apnea walking as training for freediving

You have probably heard about apnea walking as a form of training. But how does it really work? What are you actually training? There are a few specific ways to practice apnea walking. Here I will describe the method I use.

As you know from our previous posts on muscle fiber type, and muscle metabolism, different metabolic pathways and muscle fibers are active during different parts of the dive. With apnea walking, you train the ascent phase of your dives. During the ascent phase, your legs are gradually becoming more hypoxic as a result of vasoconstriction and overall oxygen depletion.

If you feel like your legs are always tired when you are coming up, apnea walking is worth a try.

Should I practice apnea walking with full or empty lungs?

Apnea walking is a good way to train the muscles under hypoxic conditions. If you do a static with full lungs, your oxygen saturation only starts to decline after several minutes. It starts to decline within a minute if you do a static with empty lungs. The same thing happens if you are walking. Empty lung apnea walks result in lower oxygen saturation, and will be shorter as a result.

Because I find the dive reflex is hard to initiate on land, I do most of my dry apnea with empty lungs. I always train with an oximeter. If the goal is 85% SaO2 it does not matter whether I get there with full or empty lungs.

For me, training with empty lungs is faster and more comfortable. If you have no problem doing long full lung breath holds on land you can fully inflate your lungs before apnea walks.

apnea walking
A simple oximeter that I use for apnea walking. It is far from perfect, but definitely allows me to track my performance better.

I use an initial static of around 30 seconds to become slightly hypoxic before I start the walk. The reason for this is that my body might maintain blood flow to the muscles if I start walking prior to the onset of the dive reflex (or HR drop). This is an obvious issue if the goal is to train the muscles under hypoxic conditions.

After my 30 seconds empty lung static I walk for approximately a minute while maintaining the breath hold. At the end of my static I try to be at SaO2 80 – 85%. I take about 10 recovery breaths, and note the final SaO2. My total recovery interval is 1:30 between walks. I get a maximum of 5 contractions per breath hold this way and I can easily keep it up for more than 10 repetitions.


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Empty lung apnea walking

Apnea walking in point form:

Get your oximeter and a timer ready. If you do not have an oximeter you can still do the exercise but it will be harder to tweak it to your needs.

  • Warm up with a couple breath holds or simply breathe slowly for a few minutes
  • Do an initial static
  • Walk
  • Take up to 10 recovery breaths (quick breaths) and relax. Your total recovery interval is 1:30
  • While in recovery the numbers on your oximeter may keep dropping. Note the lowest value. If this value is lower than your target, reduce your next static and/or walk
  • Repeat for 12 cycles

I use the ‘runtastic’ timer app for iOS in order to time my training (I am not affiliated with this app in any way).

I use the runtastic timer app for my apnea walks
I use the runtastic timer app for my apnea walks

Tweaking the exercise

Your initial static should be short enough to allow for a decent walk. If you have a strong dive reflex on land you may not even need the static. I suggest starting the static at 30 – 50 % of your onset of contraction time. For example a diver that gets contractions at 1 minute on an empty lung static should start with a static of 20 – 30 seconds. If you have an oximeter with heart rate monitor, stop the static and start the walk when you see your heart rate drop (if you see a heart rate drop at all – I often don’t).

Your oximeter will not show the current oxygen saturation. Rather, it records a moving average. Because of that you will have to keep checking your oximeter during your recovery. The lowest value should show up within 15 seconds after you start breathing. Compare this value to your target value.

Your apnea walks should be of a comfort level that you can keep up for more than 10 repetitions. The reason is that you are simply not going to induce adaptations by only one minute of hypoxic walking per training session.

Before you start training, know the risks. Any exercise involving apnea can lead to loss of consciousness, injury, or even death. Choose a safe site to train. Do not attempt this training with a heart condition. Always train with a buddy/spotter.

How do you train your apnea walks? Leave a comment!

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Training and Performance by Sara Campbell review

This post was submitted by Luca Malaguti.

In Training and Performance Sara guides you through a series of hands-on and practical exercises that apply to all facets of freedive training. I really like that Sara starts off the program by explaining a few things we tend to forget in athletic training, and especially in freediving.

Cultivating continuous improvement

Sara teaches us about the balance between sustainability and challenge. We should strive for continuous gradual improvement. In order to achieve that we need to set attainable goals that gradually lead to improvement. Setting the bar too high may lead be demoralizing, undermine our confidence, and take the enjoyment out of the dives.  Sara emphasizes that it is important to advance patiently and step outside of our comfort zone during training, but not venture too far beyond it, in order to allow for continuous progress.

'Yoga For Freediving' is a series of online yoga courses by Sara Campbell
‘Yoga For Freediving’ is a series of online yoga courses by Sara Campbell

Just as many positions (asana) in hatha yoga seem intimidating at first, breathing exercises (pranayama) can be equally daunting. Recall your first wobbly downward dog? However, Sara presents the exercises in a way that they gradually become more complicated and demanding. This I particularly appreciate. For this reason her video lessons are very effective. You have a mentor in front of you guiding your practice step by step. A lot of the exercises Sara goes over I have read them in books many times over, but having Sara in front of me belly pumping for 3 minutes pushes me to keep up with her and advance my practice so that I feel those new sensations. On my own I would probably stop after 60 seconds.

Training and Performance videos

Sara’s course contains 6 specific videos:

  • Training zone (~10 min lecture)
  • Comfort zone (~10 min lecture)
  • Pranayama – basic breath series (~45 min breathing exercise)

I found it effective to start with a few breath cycles before starting alternate nostril breathing. This way the nasal cavities are somewhat clear before the alternate nostril breathing exercise. Alternate nostril breathing is an important exercise to begin your practice with because it gets you “in the mood” to continue. Whether it is the effect of nitric oxides or just an overall cleansing sensation, this exercise first thing in the morning can really put a smile on your face.

  • Kriya – basic spinal energizer (~50 min exercise)

The spinal energizer is a truly fantastic exercise. However, if you find it painful to sit in the lotus or the partial lotus position (for example because of a knee injury, my problem), you can try sitting down with your bum touching your heels. This is known as vajra-asana or position of the diamond. This position may help to relieve some of the tension on the knees generated by the twisting.

  • Respecting your body (~10 min lecture)
  • Visualization – perfect dive (20 min exercise)

Training and Performance also comes with more than 20 extra videos and other materials to help you with your practice. The lectures and visualisation are available in MP3 format so you can bring them with you and listen to them before you dive, or on the road.

Training and performance
Training and Performance is the 4th part of Sara Campbell’s ‘Yoga For Freediving’ series.

In Training and Performance Sara goes over excellent exercises that connect movements with breath. I look forward to using them to advance my practice in freediving, while enjoying having my teacher in front of me guiding and motivating me through my practice. The way that Sara interacts with her viewers brings them by her side, and allows them to imagine a morning of diaphragm exercises on the beaches in Dahab.

Go to Yoga For Freediving by Sara Campbell (external link)

Other reviews of Yoga for Freediving by Sara Campbell

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Muscle fiber types and freediving

This article is the first in a 3-part series on muscle composition, performance, and failure during breath holding. This article is long and fairly technical. In a rush? Just read everything in bold.

Muscle fiber types and freediving

Muscle fibers use fuel in order to deliver power. This fuel is metabolized via different reactions, called metabolic pathways. There are different types of fuel, different types of muscle fiber, and different metabolic pathways to consider. The purpose of this article is to provide you with an understanding of how muscles perform and metabolize under hypoxic conditions. In light of that will come some speculation on training for freediving. What types of muscle fiber are beneficial for freedivers? What type of fuel do we need in muscles and how do we increase the abundance of that fuel?

Anaerobic and aerobic metabolic pathways

Muscles can perform under either aerobic or anaerobic conditions. Under aerobic conditions, the supply of oxygen to the muscle is sufficient to keep up steady state performance. This includes for example walking and low speed running. Under aerobic conditions, glucose is converted to pyruvate. Pyruvate in turn enters the metabolic pathways called the krebs cycle and oxidative phosphorylation to yield ATP, which is used directly as a fuel in muscle fiber. It is an efficient process that yields 34 ATP molecules per glucose molecule.

If the supply of oxygen is reduced, or the intensity increased, aerobic processes may not be able to deliver enough energy for the work required. This occurs for instance if you are sprinting. The body will require much more oxygen than it can deliver to the muscle. Thankfully, anaerobic processes take over and supply more energy to the muscle, although they can only do so for a short period of time. During anaerobic exercise, the body develops an oxygen debt that needs to be paid later (as evident from increased ventilation after a sprint). Anaerobic high intensity exercise cannot be maintained for more than about 2 minutes. Anaerobic exercise can be alactic and lactic. Alactic anaerobic exercise consumes stored ATP, which is quickly replenished by creatine phosphate. As the name implies, no lactate is produced during alactic anaerobic processes, but they cannot fuel muscles for more than 10 seconds under high intensity exercise. Lactic anaerobic metabolic pathways take over after creatine phosphate and stored ATP is consumed and have the potential to keep you going for another minute or two. Glucose is converted into ATP quickly with lactate as a byproduct. For each glucose molecule only 2 ATP molecules are produced. Because the reaction proceeds much faster than aerobic processing of glucose, more energy can be made available for the muscles for a short duration. Any exercise that takes longer than 2 minutes has a major aerobic component.

Types of muscle fiber

Humans have three types of muscle fiber. They are called slow twitch, fast twitch A and fast twitch B fibers. In some texts these muscle fiber types are referred to as type 1 (slow twitch), type 2A and type 2B. Slow twitch muscle fibers have slow contraction time and a high resistance to fatigue. They rely primarly on oxidative pathways for energy supply (krebs cycle and oxidative phosphorylation). If you are running at a slow pace or walking you are mainly using slow twitch muscle fiber.

Fast twitch B muscle fibers are the opposite of slow twitch muscle fibers. These muscle fibers have a high dependency on fuels and ATP production methods that do not require oxygen. They contain abundant creatine phosphate and enzymes that allow ATP production in the absence of oxygen. These fibers produce high amounts of force, but are sensitive to fatigue. These muscle fibers are recruited for sprinting, powerlifting and other short lived high force activites. Fast twitch A muscle fibers are an intermediate variety between slow twitch and fast twitch B muscle fibers.

Fast twitch muscle fibers are ‘fast’ because of two processes: 1) the rate of calcium release into the muscle cell and 2) the the rate of ATP breakdown. Calcium release is necessary in order to allow contraction of muscle fibers and ATP is necessary in order to ‘reset’ the muscle fiber so it can continue to contract. Hence, the rate of calcium release and the rate of ATP breakdown broadly govern the speed with which individual muscle fibers can contract. As stated in the previous section, anaerobic glycolysis is much faster than aerobic glycolysis, so ATP can be made available faster during the anaerobic conversion of glucose.

Is my muscle aerobic or anaerobic?

By now you may believe that muscles are either aerobic or anaerobic. Of course there is another complication to add to the story here. A muscle fiber will become anaerobic if the supply of oxygen is too low for aerobic ATP production. The supply of oxygen itself is controlled by many variables such as capillary density, hemoglobin concentration in the blood and oxygen saturation. Vasoconstriction, which causes resistance to blood flow, is particularly important in freediving because it restricts the flow of oxygenated blood to the limbs after the onset of the dive reflex. Because of vasoconstriction during a dive, your limbs will be partly cut off from the supply of oxygen and muscles in your legs and arms are more likely to function anaerobic.

Is my muscle fiber aerobic or anaerobic?

Our quadriceps are the most important muscles for propulsion underwater. Just like any other muscle, the quadriceps contains all types of muscle fiber, type 1, 2A and 2B. The proportion of these muscle fiber types will depend partly on genetics and partly on training. While diving, one fiber type may function aerobically and the other anaerobically. For individual muscle fibers this depends on whether they are activated (are anaerobic muscle fibers recruited or not?) and the supply of oxygen.

 Sources of oxygen during breath-hold

At the start of a breath hold, an average human has about 44% of the oxygen stored in their blood, 42% in the lungs, and 14% in the muscles. Oxygen is transported from the lungs, through hemoglobin in the blood, into the muscle where it is consumed. Where does the oxygen in the muscles come from? The muscles of diving animals (birds, mammals and humans) contain a specific oxygen carrying protein called myoglobin. Myoglobin is predominantly found in slow twitch muscle fiber.

Freedivers aiming to reach maximum performance need to increase the oxygen carrying capacity of all three reservoirs: the lungs, the blood and the muscles. Stretching and packing are the ways to carry more oxygen in the lungs. Hemoglobin is the oxygen carrying protein in the blood, and the concentration of hemoglobin can be increased (for example) by doing altitude training. The oxygen store in muscles is myoglobin, an oxygen carrying protein. The concentration of myoglobin can potentially be increased by specific exercise.

How to increase the oxygen stores of muscles

Oxygen stores of muscles can only be increased by periodically desaturating the myoglobin content of muscles. This will induce myoglobin production. Diving mammals with abundant myoglobin are commonly born with low concentrations of myoglobin. Repetitive diving causes the genesis of myoglobin over time. Can humans do the same?

For humans, myoglobin desaturation is difficult to achieve without rigorous training. In order to desaturate myoglobin, muscles need to be contracted while hypoxic (either at the end of a breath hold or during severe vasoconstriction). Eric Fattah and Sebastian Murrat have attempted to developed different training regimes in order to desaturate myoglobin and improve apnea ability. Sebastian Murrat’s training involves apnea walking and FRC dynamics, and Eric Fattah’s technique is called ‘Foundational Freediving’. The Foundational Freediving method is accessible in Eric’s e-book ‘holistic freediving’. Unfortunately, scientific evidence of an increase in myoglobin after using these training techniques has never been published, partly due to the cost of muscle biopsies.

Increasing the anaerobic energy stores of muscles

Fast twitch muscle fibers store ATP and creatine phosphate. These phosphates can readily be used for muscle contraction and do not produce CO2, nor do they consume oxygen. Hence, you can adapt the muscles for breath hold conditions by increasing the abundance of phosphates, rather than by increasing the myoglobin content of muscles. This can be achieved for example by repetitive sprints or high resistance training.

In conclusion

The muscle fiber types that can potentially be recruited for freediving are both slow twitch and fast twitch. Slow twitch muscle fiber requires a supply of oxygen, which can come from the lungs, blood, or muscle fiber itself. The myoglobin concentration of slow twitch muscle fiber can potentially be increased through specific exercise. Fast twitch muscle fiber does not require oxygen and has a high potential for the storage of phosphates. Specific exercise can increase the phosphate content of muscles.

In part 2 we will take a look at different diving animals, muscle composition, and breath hold ability, and in part 3 we will get to the actual training methods. You can find it here.

Selected links:

Selected journal articles:

  • Ferretti, G. (2001). Extreme human breath-hold diving. European Journal of Applied Physiology, 84(4), 254–271. http://doi.org/10.1007/s004210000377
  • Kanatous, S. B., Davis, R. W., Watson, R., Polasek, L., Williams, T. M., & Mathieu-Costello, O. (2002). Aerobic capacities in the skeletal muscles of Weddell seals: key to longer dive durations? The Journal of Experimental Biology, 205, 3601–3608.

Holistic Freediving by Eric Fattah

About Eric

If you have not heard of Eric Fattah but are interested in the history of competitive freediving, now is the time. In 1998 Eric invented fluid goggles, not realizing that Roland Specker had invented similar goggles in France but never marketed them. In 2001 Eric set the first world record with a monofin in constant weight (- 82 m). He dove to -80.5 m in Vancouver without a wetsuit in waters that are approximately 5 °C (41 Fahrenheit) below the thermocline. Eric dove FRC (Functional Residual Volume: diving on an exhale) for four full years, in an attempt to counter decompression sickness and registers his deepest FRC dive at Vertical Blue to 71.9 m. His experience with decompression sickness led him to implement the first experimental decompression sickness algorithm for freediving in his Liquivision dive computers.

Eric is a world class diver who has invented many techniques, and coached well known freedivers such as Branko Petrovic and William Trubridge. He wrote ‘Holistic Freediving’ in 2012, a book designed for freedivers who want to do targeted exercise to increase their CO2 tolerance, low O2 tolerance, diving reflex, and have specialized (cross-)training programs. The book is phenomenal and contains so many novel approaches to freediving that it is well worth the price tag (US$ 95).

Holistic Freediving by Eric Fattah
Eric Fattah

Holistic Freediving

One part of Eric’s phasic training that you will learn about in Holistic Freediving is ‘foundational training’. This training allows you to become better able to withstand hypercapnia and hypoxia. Even better, it will do so without pushing you to the limit and requiring many days of recovery. Forget max attempts until you have laid the foundation. You will be better able to cope with the deep dives, without having lost many training days because you needed to recover. The cross-trainings described in this book are also novel and very effective. No more Wonka tables or simple static tables. Some of Eric’s dry static tables are done with the help of pure O2 and an oximeter. Other tables incorporate exhale statics and hyperventilation. They are intense, but extremely effective. Within three weeks of doing one cycle of static trainings weekly I managed to do a 3 min 45 breathhold on an exhale. My personal best before that? One minute forty seconds.

The price of the product [95 USD] is proportional to the lifetime of secrets it contains and the extraordinary tribulations I went through to discover them – Eric Fattah

Holistic Freediving by Eric Fattah sample

Mouthfill equalization by Eric Fattah

Ask Eric for a copy below:

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Manage Your Mind by Sara Campbell

Manage Your Mind is part two of the Yoga For Freediving series by Sara Campbell. Manage Your Mind is a series of lectures and guided meditations that are designed to help you quiet your inner demons. Both the demons that tell you to go too deep too fast, and the ones that tell you to come up early.

manage your mind
Sara Campbell running freediving courses in
Dahab. Egypt. (Photo credit: Dan Burton)

Sara teaches us this with the help of Kundalini Yoga meditations, that are meant to balance your ‘positive mind’, your ‘negative mind’ and your ‘neutral mind’. Additionally one pranayama is designed to stress your body through breathhold, which both triggers your fears so you can confront them, and helps you develop the strength you need to overcome them. The awareness of your own mind and how it behaves during stress (long, deep dives, or just breath holds in general) is key if you want to improve in freediving.

Interested? Check the Yoga For Freediving website.

As with part one of the Yoga For Freediving series, Deep Relaxation, Manage Your Mind is for the freediver who is held back by the mental aspects of freediving. Even if you believe more physical training is what you need to overcome squeezes and blackout , the chances are that balancing your physical and technique training, with getting to grips with your thought patterns and how they sabotage you, is what is really going to set you straight for the longterm. Meditating in general will have positive effects on all aspects of your life, not just your freediving. Sara Campbell’s course is unique in that the lectures combined with the mediations covered in Manage Your Mind create a course that is especially geared towards freediving and very useful for those freedivers that feel the mind needs more direction during long dives and breath holds.

What you get:

  • About two hours of video lectures and meditations
  • 22 How-to videos covering the essential basics of Yoga For Freediving

Manage your mind by sara Campbell

Personal Experience

I meditate daily, and have done so for a long time. Hence, my routine was established before I did this review and so I have not followed Sara’s recommendations to the letter. However, the course did make me reflect on what mind dominates during my dives (positive, negative, neutral) and that awareness has helped me in my dives. It has not produced a measurable difference in length or depth (yet?), but my peace of mind during dives is greater, because I have a better handle on what exactly makes me stay down, or come back up to the surface.

Yoga for Freediving: Part 1

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The benefits of a freediving hang

A freediving hang is a deep static. They are best practiced while diving with a line at 10 – 15 m depth (and always with a buddy). A deep static has some amazing benefits for your body.

How to do a freediving hang?

A freediving hang can be performed simply by taking a line diving rig (a float, line and weight) into the water. Pull down until your desired depth and wait there. I usually simply hold the rope with my hand, first upside down if that is the way I neutrally float at that depth and after a little while I move myself to a ‘right side up’ position.

Why is a freediving hang beneficial?

The pressure at depth makes gases in your body react differently with your tissues and cells. Let’s say your pull-downs remove a few percent of oxygen from your body and if done on dry land you would be left with 18% oxygen in your lungs. At 10 meters depth this oxygen will react at twice the rate (2 atmospheric pressure). It has exactly the same effect as breathing 36% oxygen.

“Gas reaction rates are proportional to its partial pressure”

What effect does a hang have on the body?

This is probably a personal experience, but for me it is a combination of physical and mental relaxation. The physical part probably comes from increased oxygen perfusion within the body.  Oxygen does not enter all parts of the body naturally. Especially when you have injured muscles (or tight muscles) where blood flow is reduced, these will not be as oxygenated as a normal muscle. A massage increases blood flow and hence oxygenation. A hang will increase the oxygen available simply because of the pressure under which it is allowed to react within the body. The mental relaxation is similar to the feeling in a static at the surface. However, a deep static is more comfortable than a shallow one simply because the lungs are compressed and it is more quiet. I am better able to listen to my heartbeat when underwater. Also… it is nicer to have a look around at depth.

Keep it safe

Make sure you practice your hangs with a buddy, use a dive watch or a timer at least, and practice them on a line so that your buddy knows where to find you.

Edit 14th of June 2016. AIDA released an announcement warning freedivers of the dangers of deep hangs. Although deep is unspecified, prudence dictates I reiterate the warning here:

Warning on DEEP HANGS! Please be advised this is a very dangerous form of training even for experienced freedivers. It requires stricter safety protocols we didn’t test yet. Given this is a new phenomena, these protocols will need to be developed if this type of training gains favour in this community, but for sure we’ll need more than the usual deep diving safety. We are particularly concerned for the less experienced divers that may be tempted to do what they see on Facebook and we ask an increased level of responsibility from our athletes concerning their public posts. (https://www.facebook.com/AIDA-announcements-742763479156658/?fref=ts)

William Trubridge his comment on this post provides us with some perspective:

Like any exercise that involves depth, deep hangs have associated risk.
To introduce perspective, the following activities would all be ranked as significantly more dangerous:
• NLT/VWT/DPV freediving
• Cave freediving
• 120m+ FIM
• 100% O2 dynamic
• Deep spearfishing
There is no substitute to increasing a broad level of awareness, understanding, and adaptable safety strategies, in the individual freediver and the sport in general.
According to my log, since 2008 I’ve done 68 maximal hangs between 50-60m. In all of these I have felt entirely in control, and only on one of the 68 have I had a brief surface blackout. Deep FIM/CWT freedives are more precarious, and I expect the other athletes who have done both would agree.
The difference is not that a deep hang is more dangerous, but that it is more accessible to a less-experienced freediver. They may be able to emulate it, while not possessing the “broad level of awareness, understanding and adaptable safety strategies.” That shortfall is the problem, not the activity itself.
For now though, I will accept AIDA’s advice, and include a warning on any posts about deep hangs. I’d also advise the following safety protocols to be considered.
1. Don’t attempt any hang deeper than 50% of your maximal CWT/FIM depth, but start with more conservative depths (e.g. 30%)
2. Use a lanyard and counterballast system, and make sure your lanyard cannot entangle at the bottom while you are there.
3. Safety divers should have a clear idea of maximum dive time, and activate CB if they don’t detect the beginning of your ascent in line with that dive time. (e.g. if your max total dive time is 3 minutes, and it takes you 0:45 to ascend then they would activate CB at 2:15, if they hadn’t yet detected pulling on the rope).
Maximum dive time shouldn’t be more than 10–15 seconds longer than your previous longest clean dive to that same depth.

Finally, please note again that Freedive Wire is not a teaching institution. We merely provide news to the freediving community.

NDAC

The National Diving Centre is located 1.2 miles east of Chepstow on the A48.

There are underwater attractions in the lake, such as, you know, a helicopter, troop carrier, cruiser, and so on. There are also set lines and a training platform. the UK freediving group saltfree trains here. Get in touch with them before you go. Otherwise check out the website of the National Dive Centre.

From the North
Take the M5 South to Junction 15 – Turn west on the M4 towards South Wales – Turn onto the M48 towards Chepstow and Services – Cross the Severn and Wye Bridges and turn off at Junction 2 – Take the second exit A466 towards Chepstow and Tintern – Turn right onto the A48 at the next roundabout and continue into Chepstow. Continue through Chepstow on the A48 towards Gloucester, the National Dive Centre is 1.2 miles outside Chepstow on the left hand side.

From the South
Take the M5 North to Junction 15 – Turn west on the M4 towards South Wales – Turn onto the M48 towards Chepstow and Services – Cross the Severn and Wye Bridges and turn off at Junction 2 – Take the second exit A466 towards Chepstow and Tintern – Turn right onto the A48 at the next roundabout and continue into Chepstow.Continue through Chepstow on the A48 towards Gloucester, the National Dive Centre is 1.2 miles outside Chepstow on the left hand side.

From the East
Take the M4 West and continue past Junction 20 – Turn onto the M48 towards Chepstow and Services – Cross the Severn and Wye Bridges and turn off at Junction 2 – Take the second exit A466 towards Chepstow and Tintern – Turn right onto the A48 at the next roundabout and continue into Chepstow.Continue through Chepstow on the A48 towards Gloucester, the National Dive Centre is 1.2 miles outside Chepstow on the left hand side.

From the West
Take the M4 East and continue past Junction 23 – Take the M48 towards Chepstow – Exit at Junction 2 – Take the first exit A466 towards Chepstow and Tintern – Turn right onto the A48 at the next roundabout and continue into Chepstow. Continue through Chepstow on the A48 towards Gloucester, the National Dive Centre is 1.2 miles outside Chepstow on the left hand side.

Address: A48, Chepstow, Gloucestershire NP16, UK