When it comes to training, you have most likely heard the term ‘Metabolic Conditioning’ (or Met-Con for short) being thrown around a lot these days. The concept has been used in peer-reviewed studies, mainstream fitness mags, late night infomercials and most likely in conversation with your gym buddies – everyone seems to be doing some type of metabolic conditioning it seems… With all the attention and hype, it can be hard to distinguish whether this is just a trend like the other fitness fads that come and go, or whether this form of training has some legitimacy. The place of metabolic conditioning becomes even more unknown to us when the concept is given credit in so many different situations. For instance, one person says they do long interval running with minimal rest periods, another says they do a combination of plyometric exercises such as box jumps and broad jumps with plenty of rest between sets, while another mentions they do a circuit of strength exercises with an equal amount of work to downtime a few times each week – all in the name of met-con.

To help make sense of metabolic conditioning, it would be best to first define what the term means. Researchers in the Journal of Strength & Conditioning define metabolic conditioning as: ‘structured patterns of work & rest periods to elicit a desired response from the body’. Creating maximum efficiency of a particular energy system is normally the desired response and premise for most met-con training. And what are the particular energy systems that can be enhanced through this type of training? There are three main systems the body utilises based on the specific activity it is engaged in – let’s look at these below:


Often called the creatine phosphate pathway, this energy system is utilized by the body for speed and power type activities that are 10 seconds or less in duration (think Sprinting and Olympic Weightlifting). This system is quite powerful and has the trade-off of taking the longest time to recover between bouts – taking anywhere from three to five minutes for full recovery.


This system is intermediate in nature and is primarily used in shorter duration, intense activities (such as 800m running). The glycolytic system provides energy for activities lasting anywhere from one to four minutes. Recovery for this energy pathway takes between one and three minutes.


This enduring energy system is utilised for easy to moderate intensity work and can last for hours and hours on end. This system primarily depends on oxygen and fat as its fuel source – two things the body can get in abundance. The nature of this system allows it to replenish itself in a matter of seconds.

As illustrated, the three energy systems above are quite unique. These systems work on a continuum and there is constant interplay and contribution going on between them. Although there is no one sole energy system that is working at a time, there is however ways to train one pathway more so than others by using certain work-to-rest ratios that call upon one primary system for greater use. By using Different ratios of work to rest periods, the body can call upon a particular energy system and cause specific adaptations. Therefore, if we are looking for a desired response or adaptation, it is best to maximize efficiency of the particular energy system that delivers that particular adaptation we desire. Before we get into which specific work/rest ratios that elicit greater involvement of particular energy systems, let’s first think in terms of what activities we have traditionally used for the three energy systems and the train of thought behind these.

When most people think of training to improve one energy system, they usually only think of one training modality. For instance, most people who look to build cardiovascular endurance usually resort to one of the traditional means of cardiovascular exercise such as running or cycling. The line of thought behind this approach is to improve the cardiovascular system by constantly transporting blood to the working muscles. On the other hand, newer versions of met-con training apply a different approach to eliciting cardiovascular improvements. These newer forms of interval type training condition the muscles to better use what’s being delivered to them by improving the efficiency of the various metabolic pathways involved. What does this look like? Let’s look below at an example of a metabolic conditioning workout that can be used in place of typical ‘cardio’ activity such as running:


Kettlebell swings 60 seconds

Kettlebell Clean + Press 60 seconds

Battle Ropes 60 seconds

Squat Jumps 60 seconds

Assisted Pull-Ups 60 seconds

Dumbbell Renegade Rows 60 seconds

Rest 60 seconds & repeat twice more

With a work-to-rest ratio of 6:1, the above routine can easily replace a typical 4km run and arguably get you better cardiovascular conditioning in the process.



Some example workouts that can be used to train other energy systems are below:

Focus: Improve explosive power

Box Jumps 10 seconds
Rest 90-120 seconds

Plyometric Push-ups 10 seconds
Rest 90-120 seconds

Broad Jumps 10 seconds
Rest 90-120 seconds

Repeat 4 more times

Work to rest ratio: ~1:10


Focus: Glycolytic Gains

Kettlebell swings 30 seconds
Rest 45 seconds

Burpees 30 seconds
Rest 45 seconds

Alternating Split jumps 30 seconds
Rest 45 seconds

Dumbbell push-presses 30 seconds
Rest 45 seconds

Repeat 3 more times

Work to rest ratio: 2:3


Of course, these are only just examples. If one wants to create met-con training programs, they simply must adhere to the work/rest principles surrounding the particular energy system they are seeking to enhance.


What are some other benefits of metabolic conditioning workouts?

Aside from the aforementioned benefits met-con training offers, there are a few others worth good consideration:

  1. Increased Metabolic Rate and Fat Burning: Metabolic Conditioning has extensive scientific and anecdotal evidence for its ability to not only burn calories during a training session, but also well after the training sessions has finished. There is no workout that will burn more calories than your resting metabolic rate (RMR). Met-con workouts (particularly those involving weights) are a great way to increase exercise post oxygen consumption (EPOC). The degree of EPOC is the rate of recovery of required for metabolic rate to be brought back to pre-exercise levels. Met-con training is a great way of eliciting a greater EPOC and hence an increased metabolic rate post training. This is an effective means of fat loss as this process requires more calories to be burnt during the recovery period. As far as lean body transformation results are concerned, it seems like Met-Con has great validity
  2. Increased Strength: Apart from met-cons effects on metabolism and cardiovascular health, it is a great way to increase strength as well. Met-con workouts are often structured in a way that allow for the inclusion of multiple big and contrasting movements that enables the body to be trained more holistically. This whole-body approach also limits the chances of muscular imbalances and wear and tear on certain joints that can occur with more traditional forms of energy systems training such as distance running.
  3. More Mentally Invigorating: With multiple different ways to improve a targeted energy pathway, metabolic conditioning allows for more variety than traditional forms of ‘cardio’ and hence is more mentally invigorating for most trainees (and trainers for that matter) long term. The mental stimulation of running on a treadmill is far from that of met-con programs with their countless forms of combinations and exercises.



It’s safe to say that metabolic conditioning is more than a fad or fancy term. Based on the evidence, met-con is here to stay. Met-con is an effective way of raising the metabolic rate, burning fat, and increasing strength. Its variety and untraditional training approach make this form of training a great way to target and develop the body’s energy systems – whilst at the same time allocating an element of mental invigoration often not associated with traditional types of training. Before you go out and give met-con a go, just remember the following:

  1. What specific energy systems you are looking to develop?
  2. Pick exercises that are relevant and provide good bang for your time buck timewise (e.g. avoid isolation exercises)
  3. Pair antagonist (contrasting) muscle groups to avoid excessive joint strain
  4. Be sure to have a progressive plan in place.