Sheffield United: The big but often overlooked challenge confronting The Blades' strike-force

But the physical demands of playing at the highest level are equally as tough. Perhaps even more so. Which is why Sheffield United manager Chris Wilder, after watching his squad make a solid enough start to the new season, has granted the majority of them leave of absence at the beginning of the international break.

"We've structured the week," the Sheffield United manager said. "I'm sure plenty of them will be flying off all over the place or driving to wherever. The boys can go away. We've told them that. But they know they have to come back right for an absolute crackerjack of a game."

Although United must wait until the likes of John Fleck, John Egan, Enda Stevens and Mo Bescic return from representing their respective countries before finalising plans for the meeting with Arsenal in 12 days time, the decision to factor some downtime into the club's training schedule is part of that process.

A decade or so ago, although top-flight teams were technically superior to those in the lower tiers, the English Football League was widely recognised as being more combative, with teams sometimes able to upset their PL counterparts whenever they met in knockout tournaments by dragging them into the trenches. Those days, thanks to changes in the way academy players can be recruited, sports science and the advancement in other expensive conditioning programmes, are long gone.

A recent study by the CIES Football Observatory noted how the average height of professionals has grown across all positions since the PL was formed, with defenders returning the sharpest increase. In boxing terms, the majority of those earning a living from the game would also qualify as cruiserweights.

With half of the eight players United signed on a permanent basis after being promoted last term acquired from Championship sides, Wilder insisted the step-up must be factored in when assessing the performances of their new arrivals. Particularly, he reminded following last weekend's draw with Watford, those tasked with scoring goals.

"One thing, the big thing, is the physicality of this league," Wilder said. "How far you've got to run, the work you've got to put in, is just one thing."

"Oli (McBurnie) and Callum (Robinson), they played Championship football last year. Now they're up against absolute beasts. Physical beasts. Week in, week out, that's what they're coming up against and having to play against.

"So they can go away. We've got a few days off, then we're back in midweek to get ready for that game on the Monday."

Although McBurnie will spend the next fortnight at the Steelphalt Academy after withdrawing from Scotland's matches against Russia and San Marino, Robinson reported for duty with the Republic of Ireland following United's visit to Hertfordshire. Stevens and Egan have also been included in Mick McCarthy's plans for trips to Georgia and Switzerland, while Besic has linked-up with Bosnia and Herzegovina. Fleck, McBurnie's international room mate, is expected to win his first cap in either Moscow or Glasgow.

"The international boys are obviously going away," Wilder said. "For the others, it's a rest and then back down to business."

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