In order to understand the differences, we need to first define each of these. That in itself is a very difficult task, and one which is likely to draw criticism because everyone has a different definition of what they perceive these to be, which is often fuelled by emotion and unverifiable stories or ‘facts’, rather than logic (more on this here). So here are my interpretations of each one of these:

1. Combat sports – a combat sport is any sport where participants use hand-to-hand or weapon techniques on each other in a competition setting with a predetermined, known and agreed-upon set of rules. This can include striking (such as boxing or Muay Thai), grappling (such as Brazilian Jiu Jitsu, Judo or Wrestling), weapons (such as Fencing or Kali), or a mix of any or all of these (such as MMA, Kudo or a Dog Brothers-style of event).
There are specific rules of engagement and a known and predictable set of outcomes that is agreed upon by the competitors, i.e. a win, lose or draw, with the conditions for each of these outcomes both known and agreed upon prior to competing, for example loss via knockout, submission or points. It is important to highlight that the rules (including weight, gender, age and rank/experience divisions) are in place in order to protect the competitors and to allow for fair competition within the given set of parameters.
   
   
2. Martial Arts – I find this to be the most difficult one to define. I will therefore add the word ‘Traditional’ to this and look at traditional martial arts. They often have a rich cultural history, and generally can be said to have developed from combat styles that were used on ancient battlefields such as in Japan, India, South-East Asia, etc. An important emphasis, I feel, is the adherence to an unchanging, strict and specific set of techniques, which is rarely modified, despite advancements or changes in combat since the system was developed and codified. In other words, sword fighting remains sword fighting, and I don’t know of any Kenjutsu schools that run sessions on how to use a katana to defend against an active shooter.
While these can also be used for self defence or combat sports, they are often practiced for a variety of other benefits such as mental and spiritual development, fitness and health, preserving cultural heritage or the study of an art, in much the same way that one learns to play music or dance. 
   
   
3. Self defence – any range principles and techniques used to prevent and/or defend oneself, or another, from harm outside of training to competition. This includes physical skills, as well as environmental awareness, avoidance, de-escalation or verbal Judo, use of force, etc. The individual techniques, as well as the focus and emphasis of particular aspects from the above list, may vary significantly across locations and practitioners. The ultimate goal in this situation is survival, and more often than not, it doesn’t ‘look like martial arts’.

While they are not the same, I do believe they overlap. Think of this like having all the pieces in a Lego set, but putting them together in different ways, or having all the crayons and drawing a different picture, or knowing all the scales and chords, but playing a different tune.

Does that mean that if you know all the scales and chords and you always play classical music, you can instantly start playing Jazz?

Let’s look at an example. Roger Federer is without a doubt the greatest tennis player in history. Does that mean he is also the best player in the world at table tennis, ping-pong and badminton?
The rules are similar and the tools you use are almost identical - a ball and a racquet. Yet I daresay that if Roger Federer decided to make a career change and start playing table-tennis, while he’ll probably be better than the average punter, he won’t be able to compete against a top-ranked table-tennis player. Most people I have spoken to, when given this example, agree. Yet, when I then say that it’s the same for martial arts, self defence and combat sports the rational seems to disappear in the face of emotion.
We spend a lot of time training in a discipline and grow emotionally attached to it. We then find reasons and theories why it meets most of the criteria for each of the 3 categories (by which I mean self-defence, martial arts and combat sports, not Tennis, Ping-Pong and Badminton), often without testing any of them ourselves. You can read more about this topic here.

The recent fight between McGregor and Mayweather is a perfect example of having great skill sets in the wrong arena. Mayweather has a specialised skill set - boxing. McGregor has that in his toolbox as well, but he also needs to train in a variety of other disciplines to complete effectively in MMA. His kicks are good, his punches are good and his grappling is good. Mayweather can’t kick or grapple, but his punches are not good - they are great. When stripped of the other elements (kicks and grappling) it came as no surprise to anyone that McGregor lost. The specialist will, in the vast majority of cases, defeat the jack-of-all-trades, or a specilaist of another mode of training, when referring to a contest of specialised skills.
It would therefore make sense that:

• The self-defence expert should be better at understanding real conflict, including the ‘pre- and post-‘ elements of how real conflict develops.
• The combat sports specialist should be better at strategising and executing their specialised skill set in their chosen arena of competition.
• The traditional martial arts expert should be better at technical analysis and execution of their specialised art within the parameters of that art, as well as having extensive knowledge of the history, customs and tradition of the art.

What it really comes down to is this – each of the 3 arenas of martial arts, self-defence and combat sports comes with its own unique challenges and opportunities, rules (or lack thereof), participants, pros and cons, strengths and weaknesses, and customs and rituals. This doesn’t mean that some of the skills can’t cross over from one to the other, nor does it mean you can’t train for/in all three. Recognising the strengths and weaknesses of our style, system and skill set is incredibly important. But even more important is to understand the context or overarching theme for which the skills were developed, and the evolution (or lack thereof) of those skills.

Assuming that training in one skill set or mode of training makes you an expert in the other two is not only egotistical, but also naïve and dangerous - you could literally get someone killed, or be killed yourself.

My personal experience with my teachers and my own training has proven to me time and again that the best practitioners, those who are the true masters and experts in their fields, have trained extensively in all three, and have pitted their skill against those from other styles or modes of training time and again in order to further their understanding of their art, and have accepted, and learned from, both losses and victories.
While they often have one clear preference or training goal in mind, the exposure to multiple styles, approaches, modes of training and ways of thinking allows for a much deeper understanding of one’s own art, and as long as one continues to seek out challenges to be conquered through their art, one continues to grow and learn – which is what it’s all about.

A few thoughts to sum up, with a nice little visual aid (can you tell I used to teach maths?):

1. May seem obvious, but... Areas A, B and C are not the same:

   I don’t believe that traditional martial arts, combat sports and self-defence are interchangeable, which I am (as you may have noticed) very vocal about. I believe the misconception that they are is often perpetuated or reinforced by martial artists, whether intentionally or through ignorance.
2. Areas AB, AC or BC are overlapping:
   I do believe that the three modes of training have some overlapping skill sets. 
3. Much like Santa Claus, area ABC does not exist:

   There is no silver-bullet, kill-three-birds-with-one-spinning-kick, one-size-fits-all solution to inherently different problems. If you don’t think each area poses inherently different problems, then you missed the whole point - see point 1 (or don't, your choice).
4. Don’t use A to solve B:

   The problem dictates the solution, not the opposite. In order to develop specialised skill sets, at least past a certain point, you need to train with specialists. If you have problem B, train with people who specilaise in solving problem B.
5. If you only do A, you can’t access areas AB and AC:
   
Challenging yourself and testing your skill sets with practitioners of other styles or modes of training is critical to learning and growth. It doesn't mean you have to change your focus, at least not for extended periods of time, but it does mean try new things.

Running water never grows stale. If you are not challenged, then you are not learning. If you are not learning, then you are not growing. And if you are not growing, then you are dead... maybe as result of bringing the wrong skill set into the wrong arena. 



Stay tuned, Stay Safe,

Osu/oss