Boxing Strength & Conditioning - The Complete Guide

What Differentiates Winners And Losers in Amateur Boxing?

A 2013 study concluded that successful amateur novice boxers are able to maintain a high frequency of attacking movements, specifically the jab to the head together with punching combinations [11].

Winners were able to throw more punches and more successful punches throughout each round.

Further, they found there were no differences between winners and losers when it came to the number of defensive activities. Rather, winners were able to use their defensive actions to initiate a counterattack.

In English Regional and National level boxers, winning performance was characterized as having a larger number and success of attacking actions with fewer defenses [14].

Regional level bouts were found to have lower attacking and defensive activity compared with National level bouts likely due to the increased aerobic conditioning and skill level needed to compete over 3 x 3 minute vs 3 x 2-minute rounds.

The Most Important Factor For Boxing Performance (Conditioning)

Time To Ditch The Traditional Energy System Model

You're probably familiar with the graph below.

It shows the traditional energy system model to exercise. It looks something like this:

• •A-lactic/ATP PCr: 0-10 sec
• •Anaerobic glycolysis/lactic: 10-60 sec
• •Aerobic: 60 sec onward

The traditional energy system model assumes two things:

1. •That energy systems work in isolation
2. •That energy is provided with or without oxygen

Here's why we can't label certain exercise protocols as purely aerobic or anaerobic. And why we can't label the sport of boxing as an aerobic or anaerobic dominant sport.

Physiology Of A Single Sprint

This graph by Hargreaves & Spriet (2020) illustrates my points in one picture [44].

It shows a single 30-second sprint with the energy contributions from the 3 different energy systems.

The light green is the alactic ATP-PCr energy system, the moderate green is glycolysis or anaerobic lactic, and the dark green is oxidative or aerobic.

It shows one single 'maximal' 6-sec sprint is performed with approximately half the energy originating from 'phosphagens' (alactic) while the other half is originating from 'glycolytic' pathways.

"Of note, aerobic ATP production is also activated during very intense exercise, and 70-100% of the VO2max can be reached in an all-out 30-sec sprint.. Whereas very little aerobic energy is provided in the first 5-10 sec, ~50% of the energy contribution in the last 5 sed of a 30-sed sprint is from oxidative processes."

This shows how there's no purely aerobic or anaerobic exercise. Even short sprints show a sharp drop in muscle oxygenation with energy contributions from the aerobic energy system.

Just look at this graph of a 30 second bike sprint.

Within the first 10 seconds, muscle oxygenation has plummeted. How can this be an anaerobic (without oxygen) exercise?

But boxing isn't a sport of one all out effort. It's a sport of multiple efforts.

Physiology Of Multiple Sprints

Gaitanos and his colleagues in 1993 had subjects perform brief sprints of 10 x 6 sec w/ 30 sec recovery and found glycolysis contributes to 44% of total anaerobic ATP energy during the first sprint, but only 16% by the 10th sprint [45].

The authors theorized aerobic metabolism takes over the regeneration of energy as subsequent sprints are performed.

As each repeated effort occurs, more oxidative processes regenerate energy as muscle glycogen is used.

As Mark Glaister states in his 2005 paper "Multiple Sprint Work," *"Predominantly PCr and exclusively aerobic processes for recovery."[46]

However, this can differ based on training background. For example, Hamilton et al. (1990) put team sport and endurance athletes against each other. Both groups performed 10 x 6 sec w/ 30 sec recovery [47].

Endurance athletes exhibited a greater ability to resist fatigue which was associated with higher rates of oxygen use during sprints (aka aerobic energy).

A 1995 study by Granier and his colleagues reinforces this with the Wingate test comparing 50-200 m sprinters and 800-1500m middle distance runners [48].

The energy contributions from aerobic/anaerobic processes were similar between groups. However, the sprinters had far greater contributions from anaerobic contributions while the middle distance runners had more aerobic contribution.

But there's a big caveat to this.

The sprint based athletes had greater power output during the sprints.

Why A Higher VO2max Won't Stop You Gassing Out

Zone 2 is the golden child right now because of various health influencers and podcasters ramming it down our throats for heath and longevity purposes.

Sure, not a bad option for general health. It shouldn't be the only thing you do but better than nothing. But the consequence is this rhetoric making it into the sporting world like combat sports.

Well, to be fair, zone 2 has been pushed before this current craze but it's another level now. Regardless, here's why zone 2 may not be what you need:

1. •Primarily recruits type I muscle fibers. This isn't such a negative in the grand scheme of training since you're hopefully doing other forms of training to develop speed/power. But if you're doing crazy volumes of it, it may not be the adaptations you're after.
2. •It takes a lot of time. You need that time (and energy) to cover all aspects of these complex sports. If you're running 60 mins 3x a week, wouldn't it make more sense to use that time to train the skills of your sport where you're likely getting a similar stimulus?
3. •Which brings me to my 3rd point...If you're training enough combat sports, you're likely getting enough low intensity stimulus. Adding more is potentially diminishing returns since it takes away time you could be targeting other qualities.
4. •You need a lot of volume to continue improving aerobic capacity (aka VO2max). Repetitive movements done with volume may potentially lead to niggles/pains.
5. •Central function may not be as much of a limiting factor for sports performance. Whereas peripheral limitations likely are. Since zone 2 biases central adaptations (oxygen delivery) with VO2max being most influenced by delivery, you may be pushing for changes that don't help you on the in the ring, cage, or on the mat.

Here's why hitting the roads to improve oxygen delivery and VO2max may not be the best use of your time.

First, take a look at this graph

This is taken from our conditioning mentorship.

I have to give full credit to Dr. Andrew Usher for being a mentor and huge influence on me regarding conditioning.

It shows an incremental treadmill test to measure VO2max. The green line is heart rate, the red and yellow are muscle oxygenation for left and right rectus femoris muscles.

The point where the mouse is is approximately where VO2max occurred.

As you can see, there is plenty more left in the tank following this point indicating VO2max is likely a poor measure of performance.

Secondly, if we look at the VO2max data from various combat sports, it's not that high. Most fighters sit between 45-60 ml/kg/min from BJJ through to wrestlers, Judoka, boxers, and MMA athletes.

Considering elite endurance athletes have VO2maxes of 70+, you can see combat athletes are well below.

Further, an interesting paper categorized VO2max values and places https://journals.humankinetics.com/view/journals/ijspp/8/2/article-p111.xml

All of this to say, focusing on VO2max with zone 2 training ain't your best option. So what is?

Peripherally biasing your conditioning. Wtf does that mean? It means improving your muscle's ability to do work

The most time efficient and effective way of doing this is sprint interval training

We can look at a new review paper by Sindre Mølmen and colleagues titled: Effects of Exercise Training on Mitochondrial and Capillary Growth in Human Skeletal Muscle

They pooled papers to compared endurance, HIT, and SIT. Endurance training was classed as below the second VT/ <4mmol lactate, 87% HR max or VO2max, 75% of max power.

HIT was above these thresholds. SIT was maximal or near maximal efforts with a duration of 4-90 sec with >1:1 recovery

Let's look at some cool graphs

They found all exercise intensities led to similar increases in mitochondrial content. But SIT was 2.3 times more efficient than HIT and 3.9 times more efficient than ET.

One of the arguments against this is SIT doesn't significantly increase mitochondrial content after the first few weeks which this study found.

But we must remember these sprint interval protocols remain constant within these studies potentially leading to poorer adaptation.

Most interestingly, as shown in this graph, well trained athletes didn't show any change in mitochondrial content when expressed per hour of training after ET and HIT but not for SIT.

So that covers some of the peripheral adaptations

Now, just because you're doing sprint intervals doesn't mean you don't improve VO2max.

One of the arguments is VO2max caps out after 3-4 weeks which is shown in studies like the Tabata study and Yamagishi and Babraj https://pubmed.ncbi.nlm.nih.gov/28124388/

Sindre Mølmen and colleagues found SIT was 2.9 times more efficient than HIT and 4.9 times more efficient than ET for improving VO2max per hour trained as you can see in the graphs below. This was regardless of fitness level.

So what if VO2max caps out quickly. Doesn't that mean we need to go back to zone 2 training?

Don't Adaptations Stop Quickly?

The original Tabata study is a great illustration of this [44]. You would need to perform 20 seconds at 170% VO2max with 10 seconds rest for 7-8 reps 4 days a week.

The 5th day of the week consisted of steady-state cardio for 30 minutes with only 4 non-exhaustive 20sec/10 second intervals.

They found VO2max maxed out at 3 weeks with no significant improvements from weeks 3 to 6. Anaerobic capacity improved until week 4, with no significant changes from week 4 to 6.

It makes it seem after 3 or 4 weeks, high-intensity sprints don't provide any value. But these aren't the only metrics that matter.

Yamagishi & Babraj in 2017 put subjects through 4-6 x 15sec/2min or 4-6 x 30sec/4min sprints twice a week.

While VO2max peaked at 3 weeks (as per the Tabata study), time to exhaustion was greatest at the final week (week 9) indicating improvements in muscles ability to resist fatigue.

So who cares if VO2max didn't go up.

Performance DID!

That is what matters. We are able to work harder, longer, and faster.

Shouldn't I Do More Roadwork Since Boxing Is Aerobic?

When looking at the energy system contribution during an amateur boxing match, it becomes difficult to directly measure due to the striking nature of the sport.

Wearing gas masks during a fight is obviously not possible as taking punches to the equipment while it's strapped to your face leads to broken equipment and extra facial damage.

So, much of the research has had to focus on match simulations or measuring blood lactate values between rounds.

The current studies using match simulation have been researched well and we know that sparring and competitive fighting deliver similar physiological outcomes.

Let me preface this by saying most studies looking at the physiological responses to fighting don't tell us much.

Of course blood lactate and heart rate will be high. It's an intense activity having to continuously punch someone. And it doesn't tell us much on how to train for boxing.

But regardless, I'll run through some of the research we do have.

A 2014 study from the International Journal of Sports Physiology and Performance took 10 male novice boxers and put them through a semi-contact match simulation on the pads with typical attacking and defensive sequences [4]. 3 x 2-minute rounds were used with a 1-minute break between rounds.

They found there was an activity rate of 1.2 attacking and defensive maneuvers per second throughout the entire fight simulation.

While there was no clinching or referee stoppages, the activity rate was similar to a typical competitive bout.

The authors concluded that amateur boxing when competing in a 3 x 2-minute format has energy system contributions of 77-85% aerobic, 19-9% anaerobic alactic, and 4-6% anaerobic lactic. This definitively flies in the face of traditional thought when it comes to boxing.

Not only does the aerobic energy system provide the majority of the energy during a round, but it is also essential to recovery between rounds.

However, when compared to Commonwealth level boxers during a 4 x 2-minute match, the rate of lactate production far exceeds these elite boxers even when they threw 40% more punches than the novices in this study.

Thus, suggesting that the lower aerobic fitness level may be the reason why blood lactate was much higher compared to the Commonwealth boxers [6].

The elite Commonwealth level boxers in this study had very high aerobic capacity metrics with average VO2maxmeasures of 64 ml.kg-1.min-1. The researchers stress the importance of a well-developed aerobic energy system to not only improve recovery between rounds but to maintain performance over all 4 rounds.

In fact, a British Olympic medallist had a relative VO2max of 69 ml.kg-1.min-1 which is insane considering elite triathletes have values ranging from 70-80 ml.kg-1.min-1 [7].

Further, the high post-fight blood lactate values show the important interplay between aerobic and anaerobic lactic energy systems [6].

Again, whether this even matters is up for debate

Looking at more VO2max values of elite-level amateur boxers, Indian boxers were measured to have an average of 55-62 ml.kg-1.min-1 [8,9], Hungarian boxers an average VO2max value of 57 ml.kg-1.min-1 [10], and Lithuanian boxers an average value of 58 ml.kg-1.min-1 [13].

Not exactly elite VO2max levels.

Further, a study looking at Olympic boxing athletes highlights the importance of a well develop aerobic energy system where oxygen uptake (aka VO2max) increased from 51 to 55 ml.kg-1.min-1 from round 1 to round 3 [11].

Therefore suggesting, that to maintain effort across all boxing rounds, energy must be provided mainly from the aerobic energy system especially as rounds progress as shown in novice boxers in the first studied review in this section [12].

But this only provides half the story. It tells us nothing about what happens at the muscular level and how an athlete uses and restores oxygen. And based on the previous section, is likely the most important piece to your boxing performance.

Just look at this graph below from Usher & Babraj in 2023. It is the first study of it's kind diving deep into professional boxing physiology.

Left sied is round 1, right side is round 6.

• •AB = Bag work
• •CD = Pad work
• •EF = Sparring

The graph shows muscle oxygenation throughout each round. If you look at the sparring graphs, you'll see fighters started a lower oxygen percentage than in round 1 indicating impaired recovery.

You want the oxygen tank to restore close to it's pre sparring values so you have more to use!

Guess what is not going to improve recovery between rounds for this fighter? More low intensity, steady state cardio.

Repeating High-Intensity Efforts

This brings us to repeated high-intensity efforts. One key to boxing performance. You must be able to display high levels of power. It's your ability to repeat maximal efforts, not repeat slow efforts. I paraphrase this quote from somewhere:

"I don't care how many times you can't dunk the basketball."

So, endurance based athletes don't fatigue as fast, but can't even dunk the basketball on the first rep.

Typically, targeting low-intensity conditioning is seen as the gold standard for repeating high-intensity efforts within repeated sprint ability [24][25].

The mechanism underpinning this is the heavier reliance on aerobic processes to regenerate phosphocreatine (PCr) stores between sprints. In short, PCr is needed to convert ADP back to ATP as the muscle's energy source for contractions.

But not all research agrees with some papers only showing moderate correlations between VO2max and repeat sprint ability [26]. One reason this discrepancy may exist is the effort given by the test subjects. For example, one paper stated their subjects tended to save energy to counteract fatigue, as shown by the first sprint of each block being slower than their maximal sprint effort [24].

However, boxing is not a sport of sprinting. And high-intensity efforts often involve working against an opponent of similar weight when grappling or throwing a flurry of strikes mixed with clinching and bullying your opponent.

This is where the term repeated high-intensity effort was born and includes any effort, including sprinting like wrestling, scrambling, throwing, sweeping, and striking [27]. Interestingly, the relationship between repeated sprint ability and RHIE is poor, showing the strenuous demands of non-running activities like wrestling [28].

A study in rugby league demonstrated this using GPS to isolate and quantify collision demands from running. They found a greater reduction in collision performance (tackling) than speed, with a 14% difference [27].

Therefore, enhancing repeated high-intensity efforts will take more than hitting the pavement. You need power! And the ability to sustain it repeatedly.

What Does This All Mean?

This brings us to moving from the traditional energy system model to an updated model of substrate utliziation and central and peripheral limitations. What does this mean?

Central refers to adaptations to the heart.

Peripheral refers to adaptations to the muscles.

Substrate utiliziation refers to the fuel.

To be more precise, we could use systemic vs peripheral as systemic would also include the lungs.

The greater reduction in tackling performance seen in the rugby league study is likely due to greater peripheral demand.

The question becomes, can we address the limitation vs. blindly trying to target energy systems? Because if we throw a boat load of zone 2, steady state cardio to improve recovery between efforts but they are peripherally limited, you won't see much improvement in conditioning.

Peripherally limited athletes tend to have the range of loads during maximum lifts (e.g. 1-10RM) closely coupled and/or have a strong endurance training background where longer and shorter race paces aren't much different.

For example, an ultra-marathon and half marathon running pace.

Centrally limited athletes tend to come from strength sports/lifting backgrounds with large discrepancies between maximum rep loads.

However, combat sports are most likely limited peripherally (including boxing). This is the opinion (backed by their research and application) of Dr. John Babraj and Andrew Usher, whose protocols I'll go into soon.

Ed Baker, who was also on the podcast, mentioned combat sports are likely more peripherally demanding than centrally demanding.

We can also use anecdotes, such as when you had an absolutely disgusting sparring or shark tank session.

Your heart has little issue reaching maximum to deliver as much oxygen as possible. It's your muscles that give out.

Usher and Babraj showed this in the paper I showed above in professional boxers [23].

They found impaired mitochondrial activation, decreased rate of muscle oxygen desaturation across rounds, indicating poor recovery between rounds, and a decrease in the rate of muscle oxygen saturation across rounds, indicating incomplete muscular recovery between rounds.

So, how do we target central and peripheral adaptations? Again, nothing is in isolation so you're never purely getting one or the other.

Lower intensity = predominantly central and predominately fat as fuel

Higher intensity = predominantly peripheral and predominantly carbs as fuel.

Zone 2 steady state cardio is typically the way most coaches prescribe centrally targeted exercise.

Sprint intervals are the other end of the spectrum with other interval training modalities sitting somewhere in the middle.

Complete Guide To Sprint Intervals

Now, this does not go into the nuances and depth Andrew Usher and Dr. John Babraj go into when prescribing sprint intervals.

Instead, I'm going to give you the practical breakdown of sprint interval training so you can implement the basics right now.

• •Untrained middle aged subjects (41-43 years) performed 10 x 6 sec bike sprints with 1 minute rest twice per week. 8% improvement in aerobic capacity, 11%-27% improvement in physical function (get up and go, sit to stand, and loaded 50 m walk), and a 6% reduction in blood glucose area under the curve [8].
• •Young, healthy, sedentary or recreationally active men (19-23 years) performed 4-6 × 30-second all-out cycle sprints per session with 4 minutes of rest between sprints for 3 times per week for 2 weeks. Insulin sensitivity improved by 23%, and aerobic cycling performance improved by ~6% [9].
• •Older adults (60-71 years) performed 10 weeks of 6 x 6 second bike sprints with rest until heart rate reached 100bpm. Significant improvements were observed in pulse pressure, mean blood pressure, timed get up and go, loaded 50 m walk, and total cholesterol:HDL cholesterol ratio [10].
• •Sedentary subjects (23-29 years) performed low-intensity cycling with brief 'all-out' sprints (10 seconds in the first session, increasing to 20 seconds in the final weeks) 3 times per week for 6 weeks. Insulin sensitivity increased by 28% in male participants following the REHIT intervention, and aerobic capacity (VO2peak) increased by 15% [11].
• •Yamagishi & Babraj found similar results in VO2max increase capping at 3 weeks doing either 4-6 x 15 sec or 30 sec. However, time to exhaustion (how long you can last at a given intensity) continued increasing through the 9 weeks.
• •Usher & Babraj found 3 weeks of 3x30sec/60sec three times a week increased mitochondrial function by 162%.

Conditioning System For boxing

This is where it all comes together. You may be confused from the sciencey sections above, but this should (hopefully) clear things up.

Our goal is to accumulate time at around VO2max for central adaptations and use intense sprint intervals for peripheral adaptations. You can use more of one or the other depending on your limiter and time you have available.

The most effective and time efficient method are going to be sprint intervals as detailed in the previous section.

Here's the guidelines for each modality to cover.

Long HIIT (Central Bias): 2 - 8 x 90 sec to 5 minutes at 90-100% MAS w/ 1-3 minutes passive rest

• •8 x 2 mins @96% MAS w/ 2 min rest between sets.

Modality:

• •Rowing
• •Running
• •Cycling
• •Swimming

Short HIIT (Central Bias): 10 - 60 sec at 100-120% MAS w/ 10 - 60 sec rest (passive or active up to 70% MAS)

• •3 x (5 x 30 sec/30 sec @100% MAS) w/ 2-3 min rest between sets

Modality:

• •Rowing
• •Running
• •Cycling
• •Swimming

Sprint Intervals (Peripheral Bias): 6 - 30 sec at 1:2 to 1:4 work to rest ratio. Total work time to equal 1 - 2 minutes.

• •10 x 6 sec w/ 30 sec rest
• •6 x 10 sec w/ 80 sec rest
• •4 x 30 sec w/ 60-240 sec rest

Modality:

• •Hill sprints
• •10m shuttles
• •Bike sprints
• •Heavy bag power shots
• •Jump squats (High volume power training)

Your second (and potentially third, depending on your training schedule or conditioning limitation) will be long and short HIIT.

This is where your MAS score is put to use. Multiply your MAS by the work interval in seconds. For example, if your MAS is 4 m/s and you want to perform a 2-minute interval at 100% MAS, 4 x 120 = 480 m.

That's the distance you must cover during the work interval.

Your third day may be more long and short HIIT or a more peripherally demanding modality like sprint intervals with incomplete rest.

Where do you place intense conditioning? Typically, on your harder boxing training days you consolidate your hardest training sessions on one day and your easier sessions the following.

This is performed directly after training or separate sessions by at least 6 hours ideally. They can also be done after strength training to save time.

There is nothing wrong performing hard sprint intervals throughout your entire prep from out of camp to in camp if you're targeting peripheral adaptations.

When Does Zone 2 Cardio Become Useful?

I see 2 main uses for zone 2 cardio for boxing.

1. •The first phase of training after a fight. This allows you to move, get low-intensity exercise done, and recover from a strenuous preparation and fight.
2. •During the weight cut process. You don't want any intensity here.

That's where I see zone 2 as most beneficial. And look, you can take a zone 2 approach to your out of and in camp preparation. But finding the time to do that kind of volume on top of technical training is challenging and you may be better off using a shorter, more intense approach.

Boxing Strength Profile

The importance of lower body power cannot be understated. National team boxers were put through a series of jumps and a simulated match [3].

Turns out, vertical jump height was highly correlated with the total number of punches thrown to the body and the effectiveness of punches to the head.

Further, how quickly these boxers could produce force during the squat jump (vertical jump with a pause before jumping) correlated with rear-hand punch performance and the effectiveness of head punches.

The height of this jump also correlated with activity rate meaning those that could jump higher were more active during a fight.

Elite amateur boxers show similar traits; the squat jump and vertical jump performance explained 78% of punching impact force [4]. Meaning those who can jump higher, punch harder. This is further evidenced by elite boxers having greater contributions from the legs when throwing punches than novice boxers [5].

We also can't forget the upper body. Power generated in the bench press and bench throw show very strong correlations with punching power.

This framework provides a guideline for creating an effective strength training program specifically for a boxer.

Why You Can't Just Lift Heavy

Everything we do in the gym to prepare for boxing hinges on this simple graph (and other adaptations, but I like this visual):

It's taken from a research paper by Paavo Komi [16]. It shows the change in force by change in muscle length. Essentially, the force produced during a muscle contraction.

For a given change in muscle length (e.g., a bicep curl), we have an increase in force generated from circle 1 to circle 2. We then have the length feedback component known as the muscle spindles.

It is sensitive to the rate of stretch and "excites" the muscle to increase force production to circle 3. But the force feedback mechanism, known as the Golgi tendon organ, doesn't like this.

It pumps the brakes as a protective mechanism to dampen force production, leaving you at circle 4 for the final force output. The goal is to raise circle 4 as high as possible for a given change in muscle length.

How does heavy strength training and jumps/plyometrics help?

We can enhance the sensitivity of the muscle spindles through plyometric training. Improving sensitivity increases excitation and, therefore, force generation.

Maximal strength training desensitizes the Golgi tendon organ so it doesn't pump the brakes so early.

Untrained individuals have the Golgi tendon organ kick in too early, and this is why beginners can't express their maximum outputs in the gym. Desensitize this response by lifting heavy loads.

This is one of the adaptations showing why you MUST perform heavy resistance training AND high-velocity strength training.

Here's another graph by Kraemer and Newton, further illustrating my point and why I'm constantly preaching you can't follow a bodybuilding or Powerlifting program for boxing [17].

All sporting movements are constrained by time. As mentioned earlier on the "working effect," we must improve the ability to generate high forces in short time frames. Now, this doesn't apply as greatly to grappling actions where slow, grindy movements give almost infinite time to apply forces compared to striking actions.

Boxing and Muay Thai techniques occur within 50 - 300 ms [18]. Hence the importance of high-velocity strength training and plyometric exercises.

The graph shows different training types. The solid line represents untrained subjects. The dashed line represents heavy resistance-trained subjects (e.g. Powerlifters). The dotted line represents light resistance power-trained subjects (e.g. track athletes).

While heavy resistance-trained subjects display the greatest force, they don't display the greatest force generation at lower time points, as denoted by the 200 ms mark.

Again reinforcing the point of performing heavy resistance training AND power training. But can't you just lift the bar faster as many strength coaches will say?

Moving the bar faster is not the same as leaving the ground when jumping or projecting a medicine ball when throwing.

The black squares represent a bench throw while the white squares represent the bench press performed as fast as possible. Depending on the load, you can spend 40 - 50% of the concentric phase decelerating the barbell.

Whereas throwing the barbell allows you to continue accelerating, which powerful sporting movements mirror.

What exercises show this kind of velocity curve?

• •Plyometrics
• •Jumps
• •Throws
• •Olympic lifts

There are many other muscle architecture and neuromuscular adaptations to each type of resistance training but this overview gives you the most important bits of information about why.

Why Full Range Of Motion Is King

Muscle fiber contractile velocity is proportional to its length. Meaning how quickly your muscles contract is determined by the number of sacromeres (blocks of muscle fibers) are in a row. Muscle fiber type also plays a role here.

Sarcomeres shorten at 2x the muscle fiber length per second [19]. For example, having 10 sarcomeres in a row would shorten at 20 fiber lengths/second, whereas 5 sarcomeres would only shorten at 10 fiber lengths/second.

How do we add more sarcomeres? Eccentric training is a potent stimulus for this. Think Nordic curls for the hamstrings and weighted negative pull-ups for the upper body.

But full range of motion lifting is another method that has been shown to be superior to partial ranges of motion lifting [20].

Contractile velocity isn't the only benefit of increasing sarcomere length. You shift the angle of peak torque up and to the right, meaning you produce more force at longer muscle lengths [21].

This has the potential to reduce your risk of injury in susceptible muscle groups like the hamstrings.

It's why full range of motion resistance training IS mobility training. And no amount of static stretching will get you there (effectively).

How Do We Train To Enhance Punch Impact Force

Activation-Relaxation Kinetics

More time striking will develop this quality especially hitting the heavy bag. Using the heavy bag as a conditioning tool through some form of interval training will be your number one go to activity.

This is effective mass development. Another option are end range isometrics but they are a smaller part of the equation.

But we can still improve other physical qualities to assist with punching power. While lower body strength and power is part of the equation, it can be taken too far.

What we really want to facilitate is appropriate activation-relaxation kinetics.

To set the stage, we will start with this excellent paper by Jamie Douglas, Angus Ross, and James Martin titled Maximal muscular power: lessons from sprint cycling.

https://link.springer.com/article/10.1186/s40798-021-00341-7

Let's start with some extracts:

*As pedalling rate increases during cycling, a greater proportion of the duty cycle becomes occupied by the processes of activation and relaxation, and therefore the role of activation-relaxation kinetics becomes increasingly critical to maximising positive work and minimising negative work. *

Think of positive work as when pushing down on the pedal from 12oclock to 6oclock

Negative work is the recovery portion from 6 back to 12oclock.

*Even if rates of force development are high the minimum time required to activate and relax muscle will compromise the attainment of maximum force, and the total work that can be produced during a pedal cycle. *

Essentially saying there's only so much force you can produce in such short time frames.

*The minimum time required to deactivate or relax muscle may be 4-6 times longer than that required to activate muscle. Accordingly, unrealised work resulting from time required to relax muscle is greater than that resulting from time to activate muscle. *

"Unrealized work" refers to potential power that cannot be generated because of physiological constraints. In this instance, the longer time to relax and as cadence increases, it becomes worse. Don't worry, I'll be going into this deeper soon.

Therefore, at most pedalling rates obtained within sprint cycling, the average force production over the pedal cycle will be substantially constrained by activation-relaxation kinetics, with relaxation kinetics being the more prominent limiting factor. Ca2+ handling kinetics and cross-bridge cycling rates are the primary determinants of activation-relaxation kinetics and are primarily fibre-type dependent.

Now we are starting to unpack the strength training conundrum. Ca2+ kinetics directly influences cross bridge cycling rate.

Yes, sounds like a bunch of gibberish but put very simply, we have two protein filaments that slide past each other and bind together causing a muscle to contract. For them to bind, they need a switch which is calcium.

This binds to troponin which reveals the binding site and switches on the cross bridge action. The better calcium sensitivity, the faster you can activate/relax and the more force you can produce for longer.

Remember this as we continue.

It seems that force-based (e.g. maximum force and rate of force development) determinants of power production are more modifiable with training than velocity- and frequency-based (e.g. maximal shortening velocity, activation-relaxation kinetics and neuromuscular coordination) determinants

Excessive attention to heavy and slow strength training in the absence of explosive movements seems to be sub-optimal for power production, especially during cyclic tasks at high movement frequencies due to a slowing of relaxation kinetics.

Which brings me to Tanghe & Martin in 2019 who compared 24 weeks of heavy squatting 3x a week at 70-100% 1RM including periods of eccentric overload with an explosive training group. The explosive group performed 5 jumping exercises with bodyweight and additional load 3x/week. https://www.researchgate.net/publication/337805783_Heavy_and_Explosive_Training_Differentially_Affect_Modeled_Cyclic_Muscle_Power

These graphs show 1Hz, 2Hz, and 3Hz for ABC respectively. 2Hz is equivalent to 120RPM taking approx. 500ms. 3Hz is closer to 180-190 RPM with the entire pedal cycle taking approx. 300 ms.

In short, heavy strength training (solid gray) produced the greatest positive peak power but also led to greater negative work especially at faster speeds.

It means there's a greater deceleration during the later portion of the cycle and reduced positive power production during the subsequent stroke due to the "braking effect" during the recovery phase.

Basically, they can't switch the muscles off fast enough to facilitate speed during cyclic actions like throwing fast boxing combinations.

Not to mention, double peak muscle activation is an activation-relaxation phenomenon.

Explosive training (black dashed line) showed moderate improvements in positive work without significantly increasing negative work.

The power/frequency relationship 16-18% greater in explosive vs heavy strength training

It means training should be centered around explosive style training with some maximal strength work sprinkled in.

Eccentric overload creates the structural adaptations needed to facilitate speed and offset the potentially negative speed effects of high volume training.

Due to the short time frames for producing force when punching, anything we can do to enhance RFD is key.

Sprint intervals are likely the predominant conditioning option of choice due to its ability to improve calcium sensitivity within Type II muscle fibers and therefore, potentially facilitate activation-relaxation.

And of course the various peripheral conditioning benefits.

In my opinion, you can get away with far less heavy lifting/traditional strength training than other combat sports.

Assessments

I want to preface this with saying that I typically don't like strength standards. There's too many variables to say everyone should be above a certain threshold.

But because you may want to have something to aim for, I'll give you some VERY general guidelines. Please don't take these and think you must hit them.

Use them as general proxies for your training.

And just because you reach a certain testing benchmark does not mean you're suddenly a better fighter.

Here's some basic thresholds that can be helpful for dictating the direction of your training.

• •Back squat >1.6 x bodyweight
• •Vertical jump >45 cm (17.7")
• •Reactive strength index (40 cm box) >2.5
• •Maximal aerobic speed >4.2 m/s
• •Weighted Chin-Up >25% bodyweight additional load

These are what I'd consider absolute minimum thresholds to hit for most fighters based on research and my own experiences. Here's how a decent range will look:

• •Back squat: 1.6 - 2.0 x bodyweight
• •Vertical jump: 45 - 50 cm (17.7 - 19.6")
• •Reactive strength index (40 cm box): 2.5 - 3.0
• •Maximal aerobic speed: 4.2 - 4.5 m/s
• •Weighted Chin-Up >25-35% bodyweight additional load

Does this mean your physical training tasks are done? No.

But it gives a few basic benchmarks to aim for. How do you measure each one?

Back Squat: Multiply your bodyweight by 1.6 - 2. It should equal or be under the load you squatted. For example, if you weigh 200 lbs, you should be able to squat between 320 - 400 lbs.

Vertical Jump: Stand against a wall and reach your hand marking the wall with chalk. Jump and mark again. Measure the distance. Not an error proof exercise but an easy no equipment field test. The My Jump Lab is the best phone app for this.

Reactive Strength Index (RSI): Stand on a 40 cm box, step off. When you hit the ground, jump as high as you can as quickly as possible. Ground contact time should be minimal. I like to aim for <250 ms on the ground which you can measure with the My Jump Lab app. There's a learning curve to this exercise. Here's what it looks like: https://youtu.be/F_uhvTxSH1k

Maximal Aerobic Speed (MAS): Pick your mode or equipment for the test. Running, cycling, and rowing are the best options. Perform a 1200 m time trial. If you start too hard, you'll ruin the test. Gotta pace yourself correctly. Divide the distance by the time in seconds to get your MAS number. For example, 1200 / 300 = 4 m/s. Your MAS will be different between the exercises chosen. The benchmark is based on running but is very similar for rowing.

Weighted Chin-Up: Relatively self explanatory. Add an additional 25% bodyweight on a dip belt.

How Do Testing Results Influence Your Program?

Most people test then forget about it. Testing must influence your training. Here's some general guidelines you can follow:

• •Under strength/power thresholds: Focus on maximal strength with low-volume extensive plyometrics.
• •In range: Blend of maximal strength and power-based exercises.
• •Above thresholds: Minimal/low volume of maximal strength with higher volumes of power-based exercises.

You may have a 2 x bodyweight squat but lack reactive strength. In this case, you'd perform most of your training towards various plyometric exercise with less maximal strength volume as an example.

For MAS:

• •Under threshold: May need more volume (time dependent). A long and short HIIT approach may be preferential.
• •Within range: Compliment with sprint interval training.
• •Above range: Mainly a sprint interval training approach

Exercise Selection For Building Strength Applicable To Boxing

There are hundreds of Instagram and TikTok "gooroos" shilling you entire training programs with "specific" boxing exercises. Fuck them.

Specificity exists on a spectrum. I'm not one to say there aren't more specific exercises than others. But our goal in the gym is to enhance strength, speed, and power (and sometimes muscle mass).

Most of these exercises you're fed on social media don't have the loading or intent behind them to elicit ANY adaptation.

And that's all it really is. Are we providing the body with a strong enough stimulus to adapt?

The easiest way to think about exercise selection is to start with the 7 basic movement patterns:

• •Squat
• •Hinge
• •Push
• •Pull
• •Lunge
• •Twist
• •Carry

For boxing, I would add:

• •Throw
• •Jump
• •Plyometrics
• •Eccentric overload

Should every session have all of these? No. But your training week should cover most of these most of the time.

Strength Training Program Design For boxing

For a busy boxing athlete, twice a week in the gym is more than enough. It's all you have time for anyway.

If you're a recreational boxing athlete who goes to class for the cardio and social benefits and wants to look good, then three to four days in the gym is potentially better.

But I'm going to assume most of you reading this fall into the first camp. Boxers who's main focus is getting better at boxing.

Since you're in the gym twice a week, they should be full-body sessions. Upper/lower splits can work and, in my experience, can be quite good for older athletes (if you're careful with the volume).

But full body sessions allow you to hit muscle groups twice a week, which is generally superior for strength development.

How should these sessions look? Here's a template you can follow:

1. •Warm-up circuit
2. •Jumps/plyometrics/throws (don't have to do all 3)
3. •Full body power exercise (don't have to be every session)
4. •Heavy lower body
5. •Upper push
6. •Upper pull
7. •Core/carry/grip (don't have to do all 3)

Day 2 can be more upper body focused

1. •Warm-up circuit
2. •Jumps/plyometrics/throws (don't have to do all 3)
3. •Full body power exercise (don't have to be every session)
4. •Heavy upper body
5. •Upper body accessory
6. •Single leg exercise
7. •Core/carry/grip (don't have to do all 3)

This is a basic template that can change depending on the main goal of training. However, you can use this if you're after speed and power or maximal strength.

Just reduce your volume of speed and power exercises if strength is your goal and vice versa if you're going after speed and power.

You can also make one day more heavy strength orientated and the second day more power orientated.

Both work, up to you how you want to plan your training. I like the way I presented as if you can only get into the gym once that week, you've covered most of your bases.

You'll notice I haven't blocked strength training into only strength, or only hypertrophy, or only speed and power. It's because I don't believe in block periodization for mixed sports like boxing.

Yes, you can target one quality to maximize training effectiveness. But you blunt and diminish other important qualities you need for boxing. By the time you get to your 6th week of power/speed training, it's been months since you've done any strength or hypertrophy exercise.

Yes, there is carryover between them all. But you need more than carryover. It's why I take a vertically integrated approach to training. It means you cover all qualities within a training week.

It doesn't mean you perform maximum-volume jumps and heavy squats. It means you prioritize the quality you want to improve and reduce the volume of the others. But they are always there.

If you spend 8 weeks in a hypertrophy phase, then 8 weeks performing maximum strength, you can't hit the ground running in week 17 performing intense plyometrics and jumps. That's a recipe for injury.

What About Advanced Concepts For Programming?

Here's a quick example using more advanced concepts in a programed designed to target structural adaptations for speed alongside rate of force development and activation-relaxation kinetics.

Day 1

A1) Extensive Jump/Plyo Circuit

B1) Weightlifting Pulling Derivative

B2) Lateral Repeated Jump

C1) Lower Body Eccentric Overloda

C2) Neck

D1) Heavy Vertical Pull

D2) Accessory Push

E1) Eccentric Quasi ISO Vertical Pull

F1) Long Duration ISO Rotation At Long Muscle Length

Day 2

A1) Rotational Med Ball Throw

A2) Jump

B1) Overhead Weightlifting Derivative

B2) Neck

C1) Horizontal Row

D1) Lower Body Strength

E1) Eccentric Quasi ISO Lower Body

F1) Long Duration ISO Lateral Flexion Long Muscle Length

G1) Long Duration ISO Push-Up Long Muscle Length

Periodization Strategies To Peak For Fights

A simple heuristic to follow is to reduce total volume, range of motion (in some exercises), and focus on speed and power based exercises.

It's about having little to no residual fatigue after your strength training so you have more energy for hard boxing technical training sessions.

You should feel like you want to do more when you're done. That is a good sign you've done the session correctly.

Another strategy is trying induce a muscle fiber type overshoot.

Fibers shift between pure and hybrid fibers but to my understanding, we rarely or don't see pure Type 1 shifting to pure type 2 or vice versa.

But, you may see type IIA shifting to type I/IIA.

There's an interesting concept around targeting type IIX muscle fiber to preserve them since they are the fastest fibers.

The first point is we don't want a higher proportion of Type IIXx as combat athletes. These fibers are highly fatigable and are better suited to pure speed/power athletes.

And when we strength train, a shift happens.

A study that influenced my Masters research is by Andersen and colleagues 2005 "Changes in the human muscle force-velocity relationship in response to resistance training and subsequent detraining."

They took subjects through 3 months of strength training and found type IIX decreased from 5.6% to 0.8% while IIa increased from 34% to 39.4%.

This is not an isolated finding.

Raue and colleagues in 2004 found 4 weeks of concentric or eccentric only training (4x8 leg extension at 75-80% 1RM) led to a shift of IIXx towards IIA/IIX hybrid.

Andersen and colleagues in 1994 found sprint preparation training (2.5-3h/day, 6x/week) including heavy resistance training of 1-8 reps with 80-100% 1RM shifted muscle fiber expression from type I and IIX to IIA.

Essentially, increased activity from strength training and intervals led this shift.

Andersen and Aagaard theorize mechanical tensile load (lifting heavy weights) may switch off or downregulate the IIX gene, while upregulating the MHC IIA gene, in all of the type II fibers

And again, does maintaining IIx muscle fiber really matter?

Andersen and Aagaard make this point in their 2010 paper "Effects of strength training on muscle fiber types and size; consequences for athletes training for high-intensity sport"

From a functional point of view the disappearance of MyHC IIX with strength training may seem somewhat unfavorable since this MyHC isoform has the fastest contraction velocity and highest power production, and removal from the muscle should lead to a slowing and reduced power output of the muscle.

Theoretically that is the case when looking at the individual fiber, but when looking at the capacity of the whole and intact muscle this apparent slowing is, in most athletic settings, more than out-weighted by the increase in contractile strength, power and RFD of the trained muscle.

Now, there is a repeatable method for gaining more IIX fibers past your current distribution.

This method is doing absolutely nothing.

Yea... I know.

It's an interesting phenomenon called the overshoot phenomenon which became my research interest in my Masters thesis (and I'll cover my paper in a bit).

If we go back to the 3 month training then detraining study by Andersen and colleagues. After the large shift towards type IIA, the 3 month detraining caused IIX muscle fiber proportion to shoot past the pre intervention distribution.

It increased from 0.8% to 7.7% while the overall proportion of fast twitch fibers (IIA and IIX) increased from 40.2-44.7%.

With this came a 14% increase in maximal unloaded knee extension speed, greater force at faster velocity, and greater power at faster velocities.

It was first discussed (I believe) by Andersen and Aagaard in 2000 who ran the same protocol. 3 months training and 3 months detraining.

From approx 9% pre training to 2% post training to 17% post detraining. Can't just go months without training.

So I tried to induce an overshoot within a professional sporting session.

• •21 day taper. Skills/conditioning stayed the same.
• •3-4 days of weights a week to 1 (3 total sessions) leading into NRL season.
• •Low volume, high intensity. Power clean, overhead squat, bench press and pull.

Didn't measure muscle fiber type but we used a F-V profile as a proxy. If we saw velocity spike after the tapering period, we could assume fast twitch fiber distribution was increased.

We found significant improvements in force and power, and jump height at 25, 50, 75, and 100% BW.

It suggests a few things:

• •Resistance training volume seems to be more detrimental on force, velocity, power than conditioning based tasks.
• •What training is heavily emphasized before a taper/detraining period will likely improve most in a short taper period.
• •Practically, it means going into a fight, you could significantly reduce strength training volume 3 weeks out.
• •Potentially create an overshoot to more fast twitch muscle fibers, reduce fatigue from lifting, more time for technical.

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