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Ever feel gassed or get that ‘heavy’ feeling after putting in a high-intensity burst during Boxing?

In this article, we explain what this burn is and how we can utilise training methods to condition ourselves to perform at high-intensities more effectively.

‘The Burn’

When you perform high-intensity actions you also create an acidic cellular environment that you might know as the burn. This increase in acidity makes it hard to generate high forces because our neuromuscular system doesn’t work as well under these conditions. 

Our body has a defenceagainst this and they’re called muscle buffers. Their job is to ‘mop’ up the cellular by-products of high-intensity performance and help maintain the pH of the muscle cell. 

Our ‘Muscle Buffering’ sessions place the muscle under high-moderate acidosis which stimulates the production of muscle buffers and improves the ability to produce high-forces for longer without completely gassing out because of fatigue. 

In this article you will learn: 

  • What muscle buffering training is
  • How speed endurance training can impact on muscle buffer capability 
  • How to integrate and structure speed endurance training.

Speed Endurance Training for Boxing 

Question: What happens when you try and sprint with maximum effort for longer than 15 seconds? 

Answer: Speed declines rapidly. 

Take a look at figure 1 below. This data is taken from 5 of our boxers who performed a 30 second maximum sprint effort on our curve treadmill. We’ve split the 30 seconds into 2 parts. The first 15 seconds and the last 15 seconds. 

Each dot represents instantaneous speed at different time intervals. The dotted lines depict the rate of speed decline. 

This Graph Suggests…

  1. Peak speed occurs somewhere around 7 seconds. 
  2. The average decline in speed over the first 15 seconds is 1.3 kph (ignoring the peak speed value). 
  3. The average decline in speed over the last 15 seconds is 4.7 kph. That’s 72% greater than the first 15 seconds.

Our data above is in accordance with energy system contributions to max effort sprinting.

You can see below  that peak energy contribution occurs around 7 seconds, when ATP-PCr energy system rapidly kicks in shortly followed by glycolysis; after that there’s a rapid decline.

This happens firstly because the ATP-PCr ‘energy pool’ becomes depleted and glycolysis begins to switch off, probably due to a rapidly increasing concentration of hydrogen ions – this ‘switch off’ happens to prevent excessive cellular acidosis (caused by hydrogen ions) and help protect the cellular environment from major damage. 

What we see and feel after 15 seconds is a declining speed and strong feelings of pain, also known as THE BURN!

Similar responses have also been reported during repeated sprints. Estimates of energy contribution to repeated sprint exercise can be seen in figure 3 below.  

Much like the research above, PCr plays a large role in energy contribution to initial high-intensity actions (46%), as does glycolysis (40%). But as the number of sprints increases peak power/speed declines even in short sprints and glycolysis contribution decreases by around 30%. 

Whereas aerobic energy contribution increases and can do so by around 30% too. 

This Chart Suggests

  • In early sprints when we’re fresh we use the correct energy systems for the job
  • But as we perform more sprints we stop using the correct energy system
  • It means our ability to produce energy to generate high speed and power is a lot less
  • We see this as a lower speed/power in our efforts and increases in feelings of fatigue.

How Does This Relate to Boxing? 

Figure 4 (below) is data extracted from a piece of research that simulated 3 x 2 min of amateur boxing. Although the boxers were fairly fit in terms of their aerobic capacity, they were also novice boxers. We can see from figure 4 that glycolytic energy provision to boxing performance is a lot less than other energy systems.

This could be due to a number of reasons but mainly

1) The glycolytic potential of the boxers might be low; or
2) The participants in this research adopted a fast pacing strategy. 

From the data it’s hard to comment on point 1 but we know from the research that on average the boxers performed an attacking, defensive or technical movement every 1.2 s which by the end of the bout induced an average blood lactate concentration of 9.5 mmol·L-1. 

This indicates a significant level of activity and accompanying cellular acidosis. If you recall from the sections above, glycolysis is sensitive to acidosis and with those kinds of blood lactate concentrations we could make the assumption that even though glycolytic contribution is low it is still impaired by acidosis. 

This leads us on to another point – doesn’t this research show a low level of glycolytic energy contribution? If so, why do we want to train it?  Well, by not training this energy system you’d certainly be missing out on developing a big slice of that energy pie chart above (figure 3).

So what? Why is this important to you? 

Figure 4 gives us a bit of insight into energy provision during boxing even if it’s only from novice amateurs. 

What about the professionals? 

Well we have no data, but in the last 20 seconds of the 10th round in one of the slugfests of the 21st century, Keith Thurman and Shawn Porter detonated bombs, however, after 12 hard-fought rounds neither were able to land cleanly and get the stoppage. 

The point? You never know when you’ll find yourself in that kind of battle or have the opportunity to work harder than you ever thought for 20 s to get the win.  

The solution: Give yourself every opportunity to capitalise on each opportunity that’s presented to you. It’s one of the reasons why we focus on adaptations and not specific exercise and in part why our conditioning doesn’t always look like, or replicate, the specific demands of boxing. 

For Thurman and Porter, it’s more than likely that after 10 rounds of intense boxing their glycolytic capability was significantly reduced because of large ionic disturbances – limiting the potential energy they could draw on to be effective and limiting their force generating capability.

You never know, another 4 or 5 more effective punches for either boxer in that position could have swung the fight their way. 



In this video workshop, Danny Wilson and Dr Alan Ruddock will be sharing the science behind this highly effective training method, how to monitor performance and how to apply it to multiple training environments.


Muscle Buffers

So now we know that 20 second maximal efforts are powered heavily by glycolysis. However, glycolysis switches off due to acidosis – what can we do about it? 

In figure 5 (above) the major cause of acidosis within our muscle cell resulting from high-intensity activity is depicted as H+ (hydrogen ion). 

The green circles represent what we call ‘muscle buffers’. They are responsible for mopping up H+ and maintaining the pH of the muscle cell. When H+ appears in the muscle cell the activity of these muscle buffers increases. When we stress these systems over a period of time the number and the function of these muscle buffers increases.

This leads to improvements in the ability of the muscle cell to deal with acidosis induced by high-intensity activity. 

This type of training improves neuromuscular function, transports lactate out of the cell better, regulates H+ more effectively, enables us to tolerate muscular pain better and improves energy provision through glycolysis. 

This is important because it will enable you to: 

  1. Perform at much greater intensities, or; 
  2. Perform at a sub-maximal intensity without feeling the psychological or physiological strain 
  3. Recover faster between periods of high-intensity activity 
  4. Perform more frequent high-intensity actions with less fatigue 
  5. Dominate your opponent by varying your pace.

How Do We Train This?

In our labs, we can measure something called ‘blood lactate’, it’s very closely linked to hydrogen ions that make our cell acidic and so it’s a good marker of acidosis. A few pieces of scientific research have identified optimal lactate ‘zones’, so that’s what we aim for.

We’ve also found that we can use RPE to predict blood lactate for our target range so you don’t always need to assess blood lactate. It’s very specific to the type of session of session you’ll be performing but in your training programme we’ll give you guidance. 

If you’ve followed our programmes before then you’ll know how we like to use max effort sprints and red zone runs in our conditioning. These sessions are easy to regulate because you all you have to do is put in maximum effort (which you’ll know whether or not you’re doing) and use your heart rate monitor or RPE to know if you’re in the red zone. 

The muscle buffer sessions are creepers, in the first few reps you can’t always feel the intensity – usually because your body (as we looked at above) can deal with the metabolites that occur with hard exercise early in the session. But as the session continues you end up going one of two ways: 

  1. Fatigue can creep up on you quickly and destroy the rest of your session by slowing you down; 
  2. You can feel good and push on past your target zone and burn through the session in which case you’ll fry yourself and delayed perceptions of fatigue will hit you later that day or in the training week which can increase the risk of overtraining.  

The idea then is to find the right balance because if you hit these sessions too hard they can fry you. 

In the above examples during 1) you’ve gone off too fast and in 2) you’ve pushed past the target zone and gone too hard. There really is a sweet spot during these sessions. It’s up to you to find this. 

Speed Endurance / Muscle Buffer Sessions

The video above is a great example of how we train these qualities in the Boxing Science labs. In this session, Anthony Fowler and Jordan Gill perform a speed endurance session targeting muscle buffering, with their blood lactate monitored in between reps.

However, these sorts of sessions can be applied in any setting. They work on a treadmill, outside on the running track, or on a road with no disruption. The key is monitoring running speed and rating of perceived exertion, similar to how you would during a red zone run.

Speed Endurance- 2 minutes on, 2 minutes off

This is an effective training method for improving muscle buffer capacity. This optimises speed, recovery and muscular acidosis to target peripheral adaptations required to repeat high-intensity actions

  • 2 minutes of running at RPE 9/10 followed by 2 minutes of complete rest.
  • This is performed for 4-6 reps.
  • The running speed should be roughly 90% or 9/10ths of the maximal distance you could cover in 2 minutes, hence the RPE being set at 9/10. For our boxers, we usually set the treadmill speed at between 17 and 20 km/h.

Repeated Sprints – 12 seconds on, 48 seconds off

This is an advanced training method for improving muscle buffer capacity. This version targets neuromuscular and peripheral adaptations to repeat high-intensity actions

  • 12 seconds of sprinting at 90% maximum speed, with 48 seconds recovery.
  • This is performed for 12-25 reps.
  • After 6 reps, your RPE should be around 8. 
  • It’s important to pace yourself hold back on the early reps, to avoid burning out and impairing the intensity for later reps.

30s on 1 minute off

This is an adapted muscle buffering session designed to get him running at higher intensities, preparing for a block on the 12s on 48s off ⁣ ⁣

  • 30s on 1 minute off x 12 reps⁣
  • ⁣Target Speed = 19-21 km/h⁣
  • After 4 reps, your RPE should be 8

Speed-Endurance Circuit

This circuit was designed for muscle buffering adaptations that we normally target in our 12s on : 48s off protocol on the curve ⁣

This is tough to replicate in the gym – so we’ve adapted the session to ensure we’re targeting the session goals ⁣

  • Perform each exercise for 10 s on : 20 s recovery
  • Exercise examples, ⁣Banded Sprints, Banded Press Ups, KB Banded Swings, Medicine Ball Burpee Slams
  • No Rest – Repeat 4-5 Sets ⁣

Do these methods work?

We have seen some fantastic improvements in performance when utilising the muscle buffer sessions.

In a training camp, we often use a hybrid of 2 mins / 12s protocols to improve an athletes ability to control lactate production when performing at high-intensities.

Most sessions we monitor blood lactate to make sure we’re in the target intensity zone and analyse feedback.

Below is a comparison of Kyle Yousaf’s recent progress. Kyle has made 34% Improvements in just 7 sessions of our infamous muscle buffering session…. showing just why we use this session for FAST and EFFECTIVE results!


You can see in Session 1 that Kyle’s lactate values shoot up and beyond the target ‘Muscle Buffer’ zone… this showed that Kyle struggled with lactate accumulation despite reducing his running speed. ⁣

In Session 7, the graph shows that Kyle is in the ‘Muscle Buffer’ zone for much longer, and lactate accumulation is controlled much better. ⁣


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