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Line Diving and Spearfishing: A Symbiotic Relationship

There is a noticeable division between people who freedive on a line and those who freedive to hunt for sustenance. These two activities tend to attract very different kinds of people - those who want to submerse into body and mind (line diving), and those who are seeking a modernized ancient form of providing food for family and building friendships (spearfishing). There is nothing wrong with either, and I feel both are beneficial ways to live life. However, I don't feel like we take advantage of the fact that both lifestyles can help each other. The positive impact of line diving on your spearfishing skills should not be surprising. Perhaps less obvious are the benefits of spearfishing for line diving performance. I will be discussing both, as well as throwing in a little workout you can implement into your training to improve your diving for both sports.


Allow me to get the more straightforward connections out of the way. How can line diving positively affect our capabilities as underwater hunters? I'd like to discuss a few points such as comfortable hunting depth, carbon dioxide tolerance, as well as mindfulness and body awareness.

First let's discuss comfortable hunting depth. It's no secret that line diving is the best way to find out just how deep we can dive, but why is going deep important for spearfishing? After all, spearfishing only requires you to dive to where the fish are. In California, I commonly hear spearfishers say, "I don't need to dive deeper than 60ft. because most fish hang out shallower than that".

While this is often true there is actually a huge difference between diving comfortably to 60 feet and hunting comfortably at 60 feet. Have you ever taken a freediving class to improve your comfort at depth, thinking that you'd be able to hang out down there longer? Did you wonder why, after finishing the class, you still felt challenged to hunt at 66 feet even though you were able to reach that depth during the course?

Let's use the analogy of another sport. Think of it like a maximum weight squat. When you do maximum weight lifts, you only do one repetition with the most weight your body is capable of moving.

Imagine attempting your max squat, but instead of pushing back up immediately you had to hold at the bottom for 15 seconds before pushing it back up. Doing a max dive and then hunting there is essentially the same thing. Our body is not ready for that workout so it feels very difficult, if not impossible.

Now imagine if you cut the weight to be 33% of your max squat. What do you think your chances are of being able to do that squat with the hold at the bottom? It is probably a lot more likely you'll complete the task, and likely with much more ease than you'd expect. That's exactly what we are doing with depth training.

Our deepest comfortable hunting depth will be 33% less than the deepest dive we have ever done. So if your deepest dive is 66 feet, then you will be able to hunt comfortably at 44 feet or less. You want to hunt comfortably at 66 feet? With the appropriate education and training, time to work on reaching 99 feet comfortably.

The deeper you train on a line, the more comfortable you become hunting in shallower depths.

Second, let's discuss carbon dioxide. Carbon dioxide or CO2 is usually the strongest trigger for the urge to breathe response. However, it can also be the cause of tiredness and fatigue during long sessions in the water, which can lead to shorter breath holds and less comfortable dives. Line diving is a great way to start understanding your CO2 tolerance a little more tangibly.

For instance, you do a dive to 30 meters/99 feet and on your return to the surface you begin to have contractions (a stronger response designed to "forcefully" convince you to breathe) somewhere around 20 meters/66 feet. A few weeks later, you do the same dive, but you don't experience any contractions on the way up.

While it's important to note that other factors can also lead to contractions, this is an example of how to estimate how much your CO2 tolerance has improved.

If you're like me, having clear evidence that I'm making progress through my training is critical to my motivation to keep at it. Line diving can be one of the most tangible ways to gauge CO2 tolerance improvement. The motivation it produces to keep training will only benefit your spearfishing.

Lastly, let's take a look at how line diving improves your mindfulness and body awareness, and how that can be positively applied to your spearfishing training.

Mindfulness is a mental state achieved by focusing one's awareness on the present moment, while calmly acknowledging and accepting one's feelings, thoughts, and bodily sensations. It is often used as a therapeutic technique. Line divers are most successful when they achieve a state of great mindfulness. By training mindfulness in your line diving routines, you train your mind and body to be self-aware in the underwater realm, which results in a consistent calm and high level of focus.

So, let's talk about your feelings. No spearfisher ever likes to bring their personal life into the water. After all, this is a time for escape. What you may not realize is that whether you like it or not, you absolutely bring everything with you into the water. Some people can mask feelings really well, but a mask only covers up what still exists.

How many times has someone close to you had a bad day, and you knew without them saying anything? Was it because of changes in their behavior? Maybe their words got a little sharper. Maybe they didn't speak at all. Maybe there was a "look" about them that just seemed off.

In the same way you detect that your wife had a bad day at work, a fish can detect "danger" when you get into the water with stress or worries still hanging onto you.

One of the biggest mistakes untrained spearfishers make is looking like they don't belong underwater because we bring what I call "land problems" into the water. Fish have finely tuned senses to identify anything out of place. Their lives depend on it! When that fish encounters you in the water, either moving like you're injured or on the prowl, the fish's alarm bells go off. Off the fish goes, leaving you wondering why you never see anything to target, or can't get close enough to anything for a good shot. Your "land problems" can greatly increase these signals without even realizing you're doing it. So what do we do?

Learning how to truly enjoy a dive, regardless of life circumstances, will be your best weapon as an underwater hunter and can be practiced on a line. How do you do this? For me, practicing self awareness and mindfulness on the line has directly impacted my ability to utilize these things when I am hunting fish. Learning how to be aware of yourself and how a fish may perceive you will change your success dramatically. What better way is there to train that than being able to fully focus on your mind and body on a dive? Just like you do diving on a line.


So now we know some ways that line diving can improve our spearfishing let's briefly discuss how spearfishing might improve your line diving.

**Keep in mind I'm talking about the type of spearfishing that physically challenges you. For example, while offshore spearfishing in Southern California can be very exhausting, in most cases it is not physically demanding. The dives are generally shallow with short bottom times. If you find that a majority of your dives are easy that means your body is not being challenged enough to have any sort of positive impact on your line dive training.

First, we discussed CO2 tolerance earlier. The physically intense nature of speafishing is a great way to get exposure to higher levels of CO2. Diving for hours at a time, sitting on the bottom to wait for fish, swimming over large areas to find the right spot. When your body experiences a buildup of CO2 throughout the spearing session while also experiencing compression during breath holds, you will adapt to those levels making large volume of diving more achievable and enjoyable.

Another way spearfishing can improve your line dive training is that it will force you to pay attention to your own body. Learning how to be self-aware, and honing in on how your mind and body are reacting to certain situations. The nice part about spearfishing is that you get live feedback on how comfortable you are in the water. Body too tense? Fish stay away, if not actively trying to get away. Mind not focused? You will see your opportunity come and go before even getting your shot off. Do you look unnatural underwater? No fish to be seen in an otherwise very fishy area. By learning to analyze your own behavior and the reactions of fish, you can set yourself up with some very helpful skills that will boost your ability on a line.

**This article is purely opinion based on my personal experience. Do you agree or disagree with any of my ideas? Please use the comments and share. As a community we can help fine tune ideas together, and we can do that with constructive discussions. I will also be accepting suggestions for future topics through the comments section, so don't be shy!

Side note: if any comments seem to me hostile or inappropriate I will delete them. We do not build community by tearing each other down, nor do we want to get off topic.



Here is a workout you can do to improve CO2 tolerance. As I pointed out in this post, CO2 tolerance is a key to both line diving and spearfishing. It's a fairly simple workout, and I will explain how to do it either on a line with depth, or in a pool.


These workouts involve breath hold activities underwater, which is inherently dangerous. You MUST have a properly trained safety buddy with you anytime you are performing these type of activities, even in the pool. You will also need an appropriate dive watch to easily keep track of your surface intervals.


Because of compression and build up of nitrogen during a depth session we want to be careful not to overdo it. So for this workout we will have a minimum 1:30 surface interval (breath up time + breath hold time). This is a 10 dive workout and will be relatively short. I recommend you and your dive buddy do this workout together. One person does the workout and one is the safety. After the workout is complete you can switch. If you do any diving after the workout take a 15-20 minute break to give your body enough time to off-gas some nitrogen.

DEPTH: 15m-20m max


1) 2::45 *breathe up, 0:15 **breath hold, ***dive

2) 2:30 breathe up, 0:15 breath hold, dive

3) 2:15 breathe up, 0:15 breath hold, dive

4) 2:00 breathe up, 0:15 breath hold, dive

5) 1:45 breathe up, 0:15 breath hold, dive

6) 1:30 breathe up, 0:15 breath hold, dive

7) 1:15 breathe up, 0:15 breath hold, dive

8) 1:15 breathe up, 0:15 breath hold, dive

9) 1:15 breathe up, 0:15 breath hold, dive

10) 1:15 breathe up, 0:15 breath hold, dive

*do your breathe up however you have been taught or is most comfortable

**this short breath hold is on the surface before starting your dive

***choose either 15m or 20m target depth and stick with it the whole session

Follow the times exactly. The breathe up time starts right as you hit the surface and take your first recovery breath. The dive starts right as you complete the breath hold, and do not take a breath between the two. If you had to turn early on the dive for whatever reason the next breathe up time starts as soon as you hit the surface.

This is an exercise designed to accumulate CO2, so if you don't feel the struggle in the beginning there is a good chance you will at the end. However, if by the end it was too easy you can make this more difficult by extending the breath hold times. Increase the breath hold the next time you do it by 10-15 seconds, but keep the breath hold time the same for the whole workout (don't decide half way through to make it longer). Keep everything else the same.


This will look very similar to the depth workout. However, because we will not be diving very deep the nitrogen load won't be very different than if you were on the surface. Thus, we can be a little more aggressive with the times if we need too. This will be measured by distance, and to start things off we will stick with 25m or 25yd.

DISTANCE: 25m or 25yd (whichever you have available), or 1 pool length


1) 2::45 breathe up, dive

2) 2:15 breathe up, dive

3) 1:45 breathe up, dive

4) 1:15 breathe up, dive

5) 1:00 breathe up, dive

6) 0:45 breathe up, dive

7) 0:30 breathe up, dive

8) 0:20 breathe up, dive

9) 0:10 breathe up, dive

10) 3 breaths, dive

There are a couple ways to make this one harder. First, we can make the dive a longer distance. However, by making the distance farther you will want to adjust dives 8-10 so that the breathing time stays 0:30. Another way to make this more challenging is to "sprint" the distance by swimming as fast as you can on each dive. Again, I recommend having you and your buddy do this workout together. One as a safety for the entire workout, and then switch places.


If by the end of the exercise you are getting a very early urge to breathe, early or strong contractions, or feeling flush or hot that means you are high in CO2. This is the goal, but if it becomes unbearable back off a little so as not to sacrifice the ability to relax or your technique. And most of all communicate these feelings to your safety so they are fully aware of what is occurring on your dives.

If you enjoyed this post, or found it helpful in any way, please consider a donation. I will continue to make my perspective of freediving and spearfishing available at no cost, but a gift helps me stay motivated to keep the info flowing!

Suggested donations: $5, $10, $15

For any donations over $35 I'll throw in a 20 minute phone call to discuss the primary topic, as well as how to implement the workout in your own training routine.

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