From tackle techniques in Seattle to drills learnt in Miami, we look at how American Football is learning from rugby and vice versa

“I love this example because it encompasses everything,” says Seattle Seahawks linebacker coach John Glenn as he pauses the film, training a red laser pointer on the frozen frame of safety Delano Hill. In the clip, the defensive back is about to deliver a technically sound, walloping hit to a bracing Minnesota Vikings ball-carrier.

It’s the day before ‘Camp’ officially starts: that time of year when the NFL roars back into life, with full-team preparations for the upcoming season. Glenn is sitting in his office at the Seahawks’ plush Renton facility, running through examples of tackle techniques and training drills, and how those translate into an on-field threat to attackers. He has already shown the rest of the Seahawks staff, but tomorrow he’ll begin showing the players.

He rolls the clip on, explaining: “He’s coming from outside-in. It’s his right shoulder, so you can see his right hip tracking. He’s in the perfect position, he’s lowering as the strike-zone lowers. We want to get his cleats in the grass, ‘cos there’s power when that near foot is in the grass, but apart from that everything else is perfect.

“We’ll preach a little bit more about having the head up and eyes through the thighs, but look at how great this picture is. It’s safety, too, for the ball-carrier.

“It’s the shoulder striking hard, head out of it, getting the feet out of the grass, and bringing him down.”

Sound somewhat familiar? To anyone who learnt to tackle for rugby, there should be a resonance in those words.

Almost seven years ago, the Seahawks began looking at rugby’s tackle technique, trying to figure out how to improve their hit efficiency whilst also looking to make the game safer for their players. Glenn is in his first season as the linebackers coach, but he is picking up a familiar torch. It is fitting that Glenn continually uses the word ‘preach’ when discussing techniques – the Seahawks’ crusade for rugby-style hitting was largely driven by former assistant coach Rocky Seto, who has since moved on from coaching to become a pastor.

After running through several clips, Glenn turns and says: “So you can see we use the rugby deal – we’re all into it. We are a leverage-based, shoulder-tackling team. To break that down, we’re never asking a guy to make a head-up tackle. You’re always choosing a side, and to make it even better you’re never making a solo tackle.”

Followers of Seattle have heard a lot of talk of ‘hawks’ and ‘compressions’. The hawk tackle is, as Glenn explains, the principle of getting your nearest foot and hip close to the ball-carrier, dropping your shoulder to a height so that you can “cross punch” into their “strike-zone” – an area between the neck and knee, but preferably the thigh – wrapping, and then driving for five steps if possible.

Compression for them is, simply, a double or even triple tackle, choking off any escape route for a ball-carrier.

Over seven seasons, the Seahawks secondary defence, monikered ‘The Legion of Boom’, put these principles to fierce use. With a spate of player departures and a new defensive coordinator in charge, some acknowledge the end of an era. Head coach Pete Carroll’s dedication to the tackling principles endures, though.

Whether out of necessity or through seeing better results, more and more football minds are eyeing rugby’s tackle.

On the other side of Lake Washington, at the University of Washington’s Huskies, defensive coordinator Jimmy Lake considers the impact of his college side using rugby tackling.

In 2013, while at Idaho’s Boise State University, he and his head coach Chris Petersen brought in a local rugby team to see how they tackled. Impressed, they tried to use some of what they saw. Then, when the pair arrived at the Huskies, they decided to dedicate a lot more study over a period of years to the techniques.

“Every coach from way back when, when I was playing, was taught ‘head across the bow’ which was literally across the ball-carrier,” Lake, a former safety, says. “That meant a lot of collisions to the head. Now we’ve completely flipped everything where we are a shoulder-tackling team and our head is completely out of it. All of which we credit to rugby.

“Technically, we feel we’re in a really good spot. Our concussion rate is the lowest we’ve ever had and it’s actually made our tackling more efficient. We’ve become a better tackling team and we don’t miss as many tackles.

“We were top five for defence the last three years in the whole NCAA (division). I believe last year we were fourth in the whole country. We give a lot of that credit to our tackling.”

As well as Lake above, Glenn at the Seahawks mention concussion rates and how he hopes changing tackling style has helped reduce injury risk. Concussion and its associated miseries have cast a dark shadow over football. Rugby cannot claim to have all the answers and concussion – and specifically the risk of head injury for tacklers – is the game’s biggest concern. However, for all rugby’s flaws, football teams identifying ways to begin making their game safer must be welcomed. And there’s more.

For the upcoming season the NFL have also brought in a ‘use of helmet’ foul, stating that: “It is a foul if a player lowers his head to initiate and make contact with his helmet against an opponent.” A player could be ejected from the game for such a foul – something we have already seen in warm-up matches.

Related: ESPN writer claims NFL stars would dominate rugby

There will be teething problems, there always are as rule changes bed in. But this change is “wonderful for the sport” according to the Seahawks’ applied sports scientist Dean Riddle.

Expatriated Kiwi Riddle is part of a lucky band of scientists at the Seahawks, the team owned by Microsoft co-founder Paul Allen and based near tech-heavy Seattle. The team have developed “world-first” technologies, but are also hell-bent on scrutinising what they already have.

They brought in Atavus, the local, Waisale Serevi-backed start-up that uses ‘tacklytics’ and rugby technique to improve football’s offerings (as well as developing rugby’s). For the Seahawks they have created a rating system for each player’s tackling competency and effectiveness every game. According to Riddle, the data generated gives coaches and players an objective mechanism to evaluate defensive prowess.

There is a farther reaching aspect of what Atavus do, though, as Riddle explains: “Within high schools in Texas, there’s a certification, which every coach has to go through to coach Texas high school football. The syllabus they have to learn is delivered by Atavus and so they learn how to tackle properly.

“That’s going out to tens of thousands of coaches and that will help tens of thousands of kids. So you’ll get these kids coming through and going, ‘Oh yeah, we know the strike-zone’ and ‘I should look to get my head on the right side’. You as a rugby player would have learnt to do that naturally. Every Kiwi, male or female, knows how to make a tackle, what it looks like to make a passive tackle or a gain-line tackle or whether you are pushing them back beyond the gain-line.

“We do that instinctively, but we’ll see more and more (American) kids come through knowing that also being more discerning to ask for a breakdown of their defensive efforts.”

As much of a step closer this may be, though, you cannot forget just how different both sports are.

“It was just great to be involved in a team that made the play-offs, because it gave the whole thing we were doing so much credibility,” says collision coach Richie Gray, who is from Galashiels.

He is now working with Montpellier and Wigan Warriors in league, but Gray had his hands full back in 2016. Having spent three seasons with the Springboks, he was still helping out the South African sevens side ahead of the Olympics, while taking his first steps in assisting Scotland. He initially headed to Miami to spend a week with their coaches.

Having impressed them, he was asked to do work with some players. Then they asked him for a full season. He would fly out for seven to ten days a month, working on players’ tackling. It was a two-way exchange: Gray was developing some ideas about football technique and had some new equipment, but needed both to be tested out at the highest level; the Dolphins wanted a fresh approach.

Reflecting now, the buoyant Gray says: “Rugby’s rugby, football’s football. They’re two very, very different sports. Especially when it comes to tackling. And although there are a number of techniques that can cross over, you have to understand the game to teach the tackle within it. For example, plays are over between four and six seconds. The speed and power of the plays are so much faster and obviously laid out, so every play is down to inches.

“Also, in rugby union, if you’ve got the ball I can track you and put you down. In football you could well be taken out before you even get to the ball-carrier. Your peripheral vision, speed of movement and ability to evade before you even get to the target is totally different to rugby union.”

Which creates a unique set of problems, or opportunities for a coach. However, the biggest differences between the two worlds Gray spotted came in three forms.

Firstly, the number of staff at franchises means that football is far more likely than rugby to develop individual skills programmes for every athlete. Secondly, that everything in the NFL is far more detailed because kids in the US grow up with a playbook culture, so they are raised to consume and understand a lot of information pertaining to their team’s plays or their own skill demands. Thirdly, the training drills are so much faster.

Adam Beard, director of high performance for almost four years at Cleveland Browns was formerly the head of physical performance with the WRU. He has seen some distinct contrasts.

He says: “Over here professional sport is very different. It’s just the size of the squads. Each year you can unearth a Sam Warburton, whereas in rugby you have to develop him. Development is massive in rugby, but not here. They move players on very quickly.”

There’s more: “Football players study film all day every day. At this time of year, the quarterbacks could be in at 5.30am and not go home until 10 o’clock at night. They get used to that, day in, day out, studying opponents and their own game. I say to my guys here, ‘My rugby guys allowed me to prick and prod them, wear GPS and do all sorts of science-y stuff and they didn’t mind. But they’d never do what you do with 12-, 13-hour days.’

“You’d have a mutiny in rugby. I’d have Alun Wyn Jones trying to kill me, saying: ‘I should have been home at 3 o’clock in the afternoon!’ That’s probably the main thing. The amount of study they do here is incredible.”

Then there is the power element. Beard has seen Dan Lydiate do a 300kg parallel squat in the gym, but while that is the work of an impressive outlier, he insists that to do so in the NFL is not uncommon at all. With far less running needed, Beard says “the athlete is much more explosive and more powerful”.

He caveats this with assurances that this is due to the nature of football, and that with a greater range of demands in rugby, he sees the rugby player as one of the best athletes on the planet. But should they train differently?

Glenn shows a clip of a training set, with the Seahawks offence versus their defence. No one is wearing helmets. He talks enthusiastically about the power of the imagination as linebacker KJ Wright bursts through towards a receiver, lines him up and goes through his checklist of actions without finishing on a hit. It is all simulation.

Everyone carried out their play full-on as they would on game day, he beams, but no one is going ‘bone on bone’.

“We never bring guys to the ground in practice,” he says. “We’re really focusing on the imagination. How far can we take it?”

It is the same at the Huskies. Lake says: “Once we get into the season, there’s no live tackling in practice during the season. We use a lot of bags and also the ‘fit-tempo’ (running through plays without contact, like the Seahawks drill mentioned above). So really the guys’ legs and muscles might be tired but collisions are taken away and those really only happen on game-day now.”

Gray explains a key difference between elite rugby and the NFL, with the football league maintaining a tight grip on how much is done in training.

“There’s only a certain amount of time per week that you’re allowed to go live. That makes the way you prepare and train so much different to rugby.

“We can still go live as much as we want. We are not held to account by a union or governing body who have somebody in the building who looks at all the tape to see how much the players have done. It’s hundreds of thousands of dollars in fines if you go over it. So the way you gear up your programmes for contact, collisions, tackles, is completely different to rugby. You can’t just go and coach tackling for an hour!”

Some in the game believe that training in the NFL is too tightly controlled. Beard adds that there are restrictions on the amount of full-padded practices you do and that in ‘phase one’ of pre-season, teams are not allowed to do any football, just strength & conditioning.

Beard feels some coaches in the NFL could learn from rugby, where bosses are more open to the notion of trainer-planned periodisation – designing training throughout the year so athletes peak at certain times.

Related: Meet the Americans changing rugby in the US

There are other aspects of rugby that football could explore. Riddle gives a cryptic smile as he says: “There are some things we like!” He does reveal that the Seahawks are keen to look deeper into how successes in union develop players over time, rather than discarding them.

Going the other way, Gray is keen to look at how small aspects of how football players “destabilise bodies” can be used in counter-rucking.

There is plenty more to come in this space, but the key is to acknowledge the limits of your own understanding.

As Lake insists: “It’s funny. Ten years ago we all thought we had the answers on tackling. Then five years ago we changed everything and now we’re even better.”

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