Jaap and I made contact just over a week ago, after some conversation and a little internet stalking I began to see that he was quite an interesting guy, he has been researching freediving and potential training methods primarily on himself. Like most of us, due to the lack of studies in freediving training his finding have been mostly empirical. But his methods show some sort of scientific approach and I have to be impressed by the lengths he will go to in order to test his theories.
He was kind enough to send me his book, which I will now review for you.
The book is designed to give an understanding to the beginner to intermediate freediver of the various energy systems used in freediving and how best to train to improve those while away from the water.
For many people freediving becomes the inspiration to begin to take better care of their health, and to begin to train in a sport for the first time ever or since a long time. Most people are unaware of where to start and how to train with some specificity. Longer and Deeper will give the freediver some understanding of cross training relevant to freediving and points them in the right direction for further research.
To understand how the body is creating energy during the various parts of a dive is important information for any freediver to have. I found the explanations to be clear and to the point.
The book encourages a systematic approach to build up the various aspects of fitness relevant to freediving, which can be easily tailored to the individuals specific level.
The book also gives realistic recommendations for programming and how often to train the various aspects of freediving related fitness, with recommendations on how to tailor to your specific level. This is useful information, as there is a high rate of over training currently undergone within the freediving community, especially regarding breath holding (CO2 tolerance).
But...
Upon reading the book and recommended exercises I began to feel like it may be leading the beginner freediver in the wrong direction. Freediving in the beginning is much more about understanding what it means to go to depth, developing the techniques to get there efficiently and accepting without judging/reacting to the feelings which arise from a dive. No amount of heavy deadlifts or CO2 training will help get to rid of contractions if a diver is already getting them after 45 sec on a 30m dive (an example and recommendation from the book). Instead a change of attitude and approach is all that is needed.
Freediving is a complicated sport, so answers to issues are also usually equally complicated. In this way I find the book over simplified, in another example in the book a diver is experiencing lactic build up on a dive, the answer is to train lactic tolerance. But there is a very good chance the problem is a technique issue, for example if you feel burning in your legs during a Monofin dive, you are using the wrong part of your body to move the fin (unless you have to make adaptations to technique due to anatomy), perhaps it is a weighting issue, maybe the amount of effort and the application of force is the culprit.
So my point is that although physical fitness does have an effect on a beginner diver, it is minimal, and anyone reading this book should have a realistic expectation of how fitness will cross over into their freediving for their particular level.
Bonus info!
The most original aspects of the book are his hypothesis on potential methods to create adaptations in Blood quality and Myoglobin stores. All of this is unproven yet interesting and not without foundation. I might add that if it is time to start taking about working on blood quality and myoglobin stores, it is no longer relevant to beginner or intermediate freedivers, as I would say the energy spent on those adaptations should be the final icing on the cake of a professional freediver who has already reached his/her peak of style and relaxation.
There is some nice information regarding monitoring heart rate variability to safeguard against overtraining and reduce chance of injury. Plus some details on nutrition and supplementation.
In Conclusion
The best way for the beginner to intermediate freediver to get better at freediving, is specific and intelligent training/coaching. Nothing will ever be able to reproduce this. But for the vast majority of freedivers who spend most of their year dry, Deeper and Longer can give direction to their training and ensure they reach the water in the best possible condition.