When it comes to cardio training lots of us think of it as "just cardio". There is often no greater purpose to it other than feeling a bit out of breath & feeling your heart rate going up.
While there is nothing necessarily wrong with that, especially for a newbie trainee, much as with resistance training there should be a clear purpose of what you are trying to achieve by that particular training session.
For example, if you sign up for a 5K park run & haven't done any running for a decade, it is not a good idea to simply keep running 5K each time you exercise & just hope it gets easier. While this method could work for some people, most will find it too taxing on their body to start with so they need to build up slowly to 5K. Depending on where your fitness & body composition is currently, you may need to start by walking on a treadmill. Slowly build up the pace, the distance & the gradient to make it a little more difficult each time.
I can do 5K easy
If you can already run 5K without any trouble & you want to improve your time. Simply running 5K once, or maybe 2-3 times per week could help you improve your time. However, it is not the most effective way to spend your time. If you want to improve your athletic performance you must think & train in similar ways to athletes.
Look for weak points in your training & work on those. Try not to get sucked into always doing what you enjoy most or what you are good at, but eliminate your weaker areas.
This could be improving your top sprinting speed, your acceleration, or your lactate threshold. Everyone is different so you need to be honest with yourself about your strengths & weaknesses or pay a personal trainer to spot them for you.
Making the most of gym machines
Treadmills may be ok for beginners or you want to take it easy on your knees but it is not the same as running outdoors. This is something to be aware of as there is a great deal of cross over, however you only get better at what you train on a regular basis. If you only train on machines, your outdoor run will not necessarily get significantly better.
In my opinion the single best cardio machine that is most commonly available is the rower. It is often avoided, probably because it is difficult & exhausting, but also perhaps because people are not sure how to use it. If you are not sure, ask a trainer to show you or check your technique.
Once you are comfortable with the movement, there are many ways to improve cardio fitness that will have lots of cross over to other athletic endeavours.
Start by testing your fitness. Set the rower to 1K. After a good warm up, complete this ask quickly as you can on that particular day. This is your starting point.
Training sets can then be split into two focus points. CP (creatine phosphate) & LA (Lactic Acid) two different energy systems.
So training for the CP might be something like 10 x 8 second sprints at 90%+ of your maximum training power with 12 seconds rest between sets.
Your LA training may be something like 2-3 sets of 45 seconds at approx. 75%-85% maximum power
with 90 seconds active recovery at around 40-50% maximum power.
Each month you can up your sets you increase, length of time on LA sets can increase as well as active recovery time. Every 4-6 weeks you can re test your 1K fitness test & see how much you improve.
