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Another massive heavyweight showdown is upon us!

Anthony Joshua continues his history-making career by taking on fellow world-champion Joseph Parker.

Joshua aims to add another belt to his collection, putting his WBA and IBF titles on the line in a bid to capture the WBO strap from his New Zealand opponent.

Parker, 26, is looking to upset the odds in front of Joshua’s 80,000 crowd in Cardiff, and the millions watching around the world. Joseph Parker’s promoter has warned boxing fans not to write off the Kiwi’s chances, and rightly so, he’s undefeated and has 12-round experience.

But, over Parker’s 123 rounds, does he have enough to threaten AJ? Many believe if it gets past six rounds, Parker will have an advantage.

AJ’s weight has been a talking point since his last outing at the Principality Stadium, and in the build-up, he’s looking lighter than recent fights.

So… in another edition of ‘The Science Behind’, we take a look at: AJ vs Parker.

Quick Facts

  • AJ and Parker throw similar amount of punches – 45 punches per round
  • AJ and Parker land similar amount of power punches – 38-40% success rate
  • AJ’s Jab had a 34% accuracy prior to the Klitschko fight – now it is 27%
  • Parker’s jab against Fury and Takam was had 9-15% accuracy
  • Parker has a ‘snapping’ jab style that doesn’t land but sets up traps
  • AJ works through the gears – then maintains high work rate between rounds 4-8. This is 18.6% higher than the average heavyweight, prioritising his boxing and using the jab.
  • In the middle rounds, Parker peaks and dips by ~30% in punch volume and starts to neglect his jab.

The Takam Comparison

Analysing a fight of this magnitude requires planning, thought and some educated guess-work, especially when anything can (and does) happen in boxing.

It’s always great when two fighters have faced the same opponent:

Anthony Joshua took on Carlos Takam as a replacement for Kubrat Pulev in his last fight, and he’s also a former opponent of Joseph Parker (May 2016).

AJ stopped the Frenchman in 10 rounds, whereas Parker dominated in a comprehensive, unanimous points win. Our performance analyst, Chris Pitsikas, has extracted the punch statistics from both fights using video-based performance analysis techniques. 

From a fans point of view a TKO win is often seen as a better win that a points victory, but we’re really interested in the performance within those rounds. Looking at the numbers, AJ had a much higher success (33%) than Parker (23%) against Takam. In terms of volume, they were quite similar, with AJ and Parker throwing around 45 punches per round.

However, looking at the data much closer, Joshua works through the gears well and manages to maintain his punch volume – between rounds 4-8 he averages 54 punches thrown per round – thats 22% above the heavyweight average and what Parker averaged against Takam (45 punches per round).

As we delve deeper, we notice different trends as AJ maintains his punch volume, whereas Parker peaks and dips.

When Parker has a high-intensity round, he seemingly drops off for the next one – this happened three times between rounds 4 and 9  – averaging a decline in punch volume of -30%.

What’s Happening Physiologically?

Dr Alan Ruddock explains…

Although heavyweights hit hard, they pay the price concerning energy. The bombs they throw are very ‘inefficient’, and heavyweights don’t have the aerobic capacity or specific conditioning to be able to deal with the magnitude of cellular disruption that occurs when they exceed their critical intensity. 

So when Parker starts to throw bigger shots, he needs to somehow cope with the metabolic demands. Or not, as in the case we’ve highlighted above. There are three options for Parker when he steps up the intensity: 1) decrease the number of power shots; choose a different technical strategy or do both (more on this below). 

In contrast, AJ works through the gears stepping up his power punches each round until about halfway. After round 6, he realises that he might need to adjust his efforts and so he changes his pacing strategy from throwing power shots (which are energetically costly) to throwing jabs. This has two purposes;

  1. he can still dominate tactically and win rounds and;
  2. it allows him to partially recover (or at least have more energy than his opponent) in the later rounds. 

So what’s the ideal pacing strategy for a heavyweight? 

Throwing bombs early on optimises the potential force of a punch and increases the likelihood of a KO/TKO. 

BUT this is risky from a technical perspective and a fitness perspective because if the tactic doesn’t work, then there’s a lot of hard graft to be done in the later rounds and this obviously increases the risk of gassing out. 

If a heavyweight has the fitness and the technical ability then another approach might be to work behind the jab for the first half of the fight, win rounds and be ‘efficient’. 

This more economical tactic can then be utilised in the second half of a fight. Strength and fitness reserves can be used to increase intensity and volume of power punches and perhaps take advantage of an increasing number of technical flaws in the opponent. These gaps usually open up from midway in closely matched heavyweights and so this strategy increases the likelihood of a late stoppage or KO’s and conserves energy for a potential war in the final rounds.

Joshua’s Superior Jab

Prior to the Klitschko fight, AJ had a pretty impressive jab average conversion with 34.4% of his 21 jabs per round. To put that in perspective – the heavyweight average is 25.5% and Klitschko, renowned for his effective jab, averaged 30.1%.

However, it would be a challenge to maintain this rate when facing better opposition. Against Klitschko and Takam, AJ averaged 22 and 27%, respectively.

Still an impressive figure – but how does this compare with his New Zealand counterpart. 

Parker tends to throw a similar amount of Jabs to AJ, however, lands a lot less. In the two fights we’ve analysed against Takam and Fury, Parker lands 9 and 15% of his jabs!

That’s an average of 2 per round!

Let’s have a closer look at the trends of the jab for both Champions.

In a recent interview, AJ was quoted when discussing the Takam fight “I have learnt how to do the distance, managing my work and how I pace myself over the 12 rounds”.

The past two fights have taken AJ to the 10th round, and you can see similar trends (although the numbers are quite far apart due to his epic battle with Klitschko). AJ tends to work through the gears, peak with his power punches in the middle rounds, then alter his approach by using his jab more.

This suggests, as an energy saving tactic, AJ builds up his power punches early on but then decides to box smart, using the jab to get through the rounds.

Parker’s jab approach is the polar opposite! He uses the jab early on, then seemingly neglects it in the middle rounds as he looks to throw and land more power punches.

What does this suggest?

  • In the middle rounds, when maybe AJ is feeling fatigued, he manages his energy well and maintains good boxing skill.
  • Parker, on the other hand, seems to neglect his boxing and look to land power shots.

What does this mean for the fight?

AJ has a superior height and reach advantage on Parker, and the New Zealander will need to be on the front foot to work on the inside.

Parker needs to use his jab to set up these attacks. However, he may start to neglect the jab when fatigued – meaning he’d be stepping forward without throwing.

This will allow AJ to dominate the middle rounds – outboxing and landing heavy counters. 

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It’s not just about the numbers…. AJ and Parker have very different Jab styles. 

The reason why Parker scores so little punches is due to the way that he throws and utilises it during his attack.

He has the ‘Larry Holmes’ style of using it as a ‘speed’ weapon. He flicks/slaps the jab out rather than putting force behind it like AJ.

He throws the same amount as AJ, but doesn’t prioritise its success over landing the rest of the combination. You could say that Parker sacrifices his jab, or at least uses it as a distraction, in order to land a power punch.

Take a look at the video below to get a more detailed understanding of how Parker uses his jab.

What does this mean for the fight?

When moving in, Parker will look to throw two or three jabs to set up an attack.

A simple option for a lighter AJ could be to utilise his footwork to take a short step back and set up counter punches. Although very unlikely, AJ should avoid what Hughie Fury did, where he tried to create too much distance inviting Parker to come forward.

AJ should look to sting him with sharp counter punches if Parker uses a similar game plan.

Also, there’s another issue around Parkers jab

Elbow Problems for Parker?

In a recent article by Sky Sports News, Promoter David Higgins opens up about his boxer undergoing elbow surgery late 2017.

This may affect Parkers jab, as healthy elbow function is vital for an effective jab.

Plus, his style does not compliment the elbow issue – Parker’s punches are thrown at relatively high velocity and force yet often miss the target. Here problems can arise because the bicep muscles are not able to effectively decelerate the punching arm, therefore, a lot of force goes through the elbow musculotendinous unit.

What can you do to protect yourself from Elbow injuries?

First of all, you’d work as a team to decide how to combat a recurring issue. Like we’ve just explained, the style of Parker’s jab is probably the cause of the injury – so if he continues with this style he’s likely to have continuing problems in his career. The team would have to decide whether this style was effective enough to try and manage or alter his style to avoid an injury that’s limiting performance.

Despite fighting style, elbow injuries are common in boxing. Here are a few considerations you’d want to make to combat elbow injuries.

  • Manage training loads – make sure to periodise your week with high/low-load training days for boxing – integrate non-punching days or sessions that focus more on technique and accuracy rather than speed and power.
  • Loosen Up – Don’t just focus on the elbow – as this may be injured due to compensating tightness/weakness in other areas of the body. An elbow injury could occur due to overload from tight shoulders, ineffective hip extension, or underactive biceps/triceps.
  • Isolated Eccentrics – We do have to look at isolated work around the elbow – controlled extension and flexion can help improve the function and integrity of the ligaments, tendons and muscle that help keep the elbow healthy. Try out isolated one-armed bicep curls and tricep extension for 12-15 reps at a slow tempo – 4-6 seconds on the eccentric action.

Find out more about Boxing Injuries and Rehab with our Combat Conditioning Conference.

Physiotherapist Rob Madden presents a fantastic workshop on The Boxer’s Shoulder: Considerations Around Injury Prevention & Rehabilitation.

Rob, who works with Anthony Joshua and James DeGale, explains the science behind common shoulder injuries in Boxing, how to screen athletes and his top exercises to protect the shoulder from injuries.

Details of the conference will be released soon, sign up to our VIP list to receive updates and access an exclusive discount.

Did Fury Provide The Blueprint?

Parker was introduced to the UK public in his second WBO title defence against Hughie Fury, cousin to former unified champion Tyson.

Hughie looked to emulate Tyson’s ‘masterclass’ performance against Klitschko to reintroduce the WBO strap into the Fury fold. Hughie worked at range using his height, reach and dynamic footwork to elude Parker’s aggressive assaults. This frustrated Parker, who struggled to pin Hughie down in the fight.

Many felt that Hughie did enough to win the fight, however, Parker’s front foot approach was favoured by the two judges and one couldn’t split the two – giving the New Zealander a majority points win.

Although there were a number of people up in arms at the outcome, there were plenty of critics felt that Hughie could’ve done more in the fight to influence the judges scoring. The footwork and tactics were an effective defence – but crisp counters and effective work on the inside were lacking.

AJ can take a lot from this – he could look to employ similar tactics that suit his style –

  • Box on the outside and set traps
  • Use feet defences but make sure to plant to land counters
  • Hold on inside – but make sure to score with body shots and uppercuts.

To employ these tactics… AJ would have to be a lot lighter and more dynamic in his previous fight with Takam.

Fortunately, the Champ is looking in fantastic shape.

AJ 2.0: Lighter and Faster

A lot of the pre-fight talk has been around what weight Anthony Joshua will come in at, following criticism of the WBA and IBF champ looking ‘too bulky’ and ‘too sluggish’ against Carlos Takam.

From the outside looking in, AJ tipping the scales at 18 st and 2 lbs would be a cause for concern – especially when you consider the 24 lbs he has put on since his debut in 2013.

Boxing Science always like to take a closer look at controversial issues, and we put together an intriguing article Anthony Joshua: Size Matters’, where we highlighted that Joshua’s increase in body mass actually matched the rate of change in his opponents fighting weight.

We also stated that this has been a controlled process by his world-class team, especially when you compare his weight increase to previous heavyweight champions.

However, it seems that AJ has opted to come in lighter for this fight. Also judging by social media activity, AJ has been running a lot more in oppose to using the Watt Bike as the main conditioning tool.

When you consider the points we have discussed in previous sections of this article – you’d say that the team have got it spot on again.

Why can size be an issue for fitness?

When an athlete increases in body mass, whatever composition (amount and type of lean tissue, fat, water), it will increase their energy expenditure.  Each shot thrown, every head slip and foot defence will require relatively more energy to perform.

In heavyweight boxing, a large proportion of actions are forceful whole body movements requiring significant amounts of energy. Most modern-day heavyweights will have a good sized engine, but this engine needs to keep up with an increase in size to match new energy demands.

Let’s work through a simple example:

We quantify fitness using the physiological metric of aerobic capacity in litres of oxygen taken up by the active muscles and used each minute (VO2 in L/min).

We can compare this value between athletes if we divide by their body mass (VO2 in ml/kg/min).

Let’s say our boxers aerobic capacity is 5.5 L/min. His relative oxygen uptake is 53 ml/kg/min when he turned pro at 104 kg. After a few years, let’s assume his fitness has stayed the same since he turned pro but his weight increased. At 115 kg his relative oxygen uptake is 48 ml/kg/min.

At the heavier weight, his engine is relatively smaller. We haven’t considered the fraction of that capacity he can box at, or how well he can deal with shifts from predominantly aerobic to anaerobic metabolism or the neuromuscular demands involved in his contests but what this illustrates is that:

“At the heavier weight, the boxer’s engine is relatively smaller.”

His ability to use oxygen for energy production would be relatively less.

This means that he’ll need to rely on other energy sources – which, after time, make it much more difficult for muscle cells to do their job of producing force – manifesting in what we see as fatigue.

So why is the weight loss and extra running work such an advantage for AJ?

It looks like AJ has introduced more running into his programme probably because of two reasons:

  1. AJ doesn’t have much fat to shift, so the only way to decrease his weight is to sacrifice muscle mass. Replacing a strength training session or two with running enables him to decrease the anabolic responses of strength training with the relatively catabolic response of running. This obviously has to occur with a diet lower in protein and overall energy so that he’s in a slight negative energy balance. The result is a decrease in weight.
  2. Running is also a superior mode of training for boxers compared to cycling, but if you weigh close to 18 stone, running is very stressful on the joints and presents an injury risk. As AJ drops weight the total force transmitted through key lower body structures of the hips, knees and ankles becomes less and the risk:reward of injury:fitness becomes more favourable to fitness.

We’re happy to see AJ running again because it means his fitness is only going to improve and that’s going to lead to better performance in the ring. He’s always had the KO power and that will still be there, but, there’s going to be a very dangerous AJ, who’s fitter, lighter and just as strong as ever before.

Expect to see a very sharp Anthony Joshua on the 31st March.

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  • AJ works through the gears in the early rounds and maintains punch volume in the middle rounds.
  • Parker peaks and dips in his work through the middle rounds – he will have a busy round followed by a decrease in punch volume – 30% on average.
  • AJ’s Jab is far superior to Parkers, landing 27% on average in comparison to Parkers 9-15%.
  • AJ uses the jab to manage his energy and win rounds – whereas Parker starts to neglect it through the middle rounds.
  • Parker’s jabbing style may have caused elbow injuries – this may be an issue when trying to set up attacks.
  • Fury showed the way to beat Parker – AJ is lighter and fitter and can execute similar tactics.

Boxing Science Prediction

Our predictions are often accurate, but we have come under a bit of criticism for being too vague. So we have decided to be more precise with our Boxing Science prediction.

Considering the fighting styles, punch statistics and training approach – we predict that Anthony Joshua will win via TKO between rounds 7-10.

Parker’s peaks and dips in energy, neglect of the jab will suit a fitter, lighter and faster Anthony Joshua.

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