Russia will be severely hampered by their arduous travel schedule at the FIFA World Cup, according to former team doctor Yuri Vasilkov.
Fabio Capello's side arrived in Sao Paulo, Brazil on Sunday after a long-haul flight from Moscow, and will again be boarding planes to Cuiaba, Rio de Janeiro and Curitiba for their three Group H matches.
Vasilkov, who travelled with Russia to South Korea/Japan for the 2002 finals, said such a drastic change in time zone was a significant factor in the national side's preparations.
"There is a whole new science about long-distance travel. If we move by north to south – to Madagascar, for example – it's easy. Our bodies don't need to adapt," Vasilkov told UEFA.com.
"But if we go east or west and spend more than four hours in the plane, then our bodies find it harder to adapt to new circumstances."
Capello has reportedly gone lightly on his charges in their first hours in Brazil, and Vasilkov said that was a sensible move from the former England boss.
"After long flights, players shouldn't be training really hard," he said.
"They need time to recover. Also, we have noted that it is harder to sleep if you fly east to west."
Vasilkov said while players should not be consuming 'fancy food' at a World Cup, he recounted treating some of their squad members 12 years ago.
"Fancy food is not welcome at these tournaments as the pressure on players' bodies is very high anyway," he said.
"We had to take individual needs into account, though.
"Back in 2002, I took some black caviar with me to spread it on bread to make some players happy. Believe me, it wasn't just for me."
Russia's team chef Nino Graziano said he will provide only nutritional options for the players.
"We will say no to fatty food," Graziano said.
"Pasta, chicken, fish and rice with vegetables are welcome and of course meat, which is very good in Brazil.
"We will give the players plenty of fruit too. The team's mood and results depend a lot on the quality of their diet."
|Toranzo did not lose toes - Huracan president|
|Willian expects Terry to depart Chelsea|
|Mexico 2 Senegal 0: Duenas, Pizarro inspire win|
|Copa Libertadores Review: Sao Paulo, Racing qualify for group stages|
|Liverpool should be transparent with Sturridge injuries - Owen|
|FFA hands Wanderers fine and suspended points deduction|
|Luis Enrique: I had to give my voice a rest|
|Silva: I was not kicked off Marseille team bus|
|Blanc could sign PSG renewal by end of week|
|PSG drawn against familiar foes Saint-Etienne in Coupe de France|
|Neville confident Valencia fans will be back|
|Guardiola praises beaten Bochum|
|Coupe de France Review: Ibrahimovic sends PSG through, Nantes win thriller|
|I love penalties - West Brom´s shootout hero Foster|
|Ross County 0 Hearts 3: Dauda dazzles in valuable victory|
|Bayern Munich avoid Borussia Dortmund in DFB-Pokal semi-finals|
|FC Heidenheim 2 Hertha Berlin 3: Ibisevic at the double in DFB-Pokal|
|Hart: We will fight for Pellegrini all the way|
|Peterborough United 1 West Brom 1 (aet, 3-4 on pens): Foster spares Premier League team´s blushes|
|Paris Saint-Germain 3 Lyon 0: Ibrahimovic fires holders into last eight|
|Valencia 1 Barcelona 1 (1-8 agg): Kaptoum breaks record with late leveller|
|Bochum 0 Bayern Munich 3: Lewandowski double helps book semi-final spot|
|Colour clash forces Stoke to produce new kit|
|Hernandez to miss Darmstadt match with muscle injury|
|Stoichkov backs ´smart guy´ Neymar to stay at Barcelona|
|FSG´s letter of apology to Liverpool fans in full|
|Huracan bus overturns following Copa Libertadores clash|
|Liverpool scrap ticket price increases following fan backlash|
|Oviedo hopeful of new Everton contract|
|Zoff: Juventus-Napoli a Scudetto match|
|Bolton chairman Phil Gartside dies aged 63|
|Palermo turn to Bosi after Barros Schelotto exit|
|Ben Arfa considered retirement from football during exile|
|Bilic: We paid the price for cup progress|
|Griezmann happy to stay at Atletico|
|Wales to face Sweden in final Euro 2016 warm-up|
|Varela hopeful of long United career|
|Ki: I had ice on my face for two days|
|Niasse settling in well, could face West Brom - Martinez|
|Stevens leaves Hoffenheim on health grounds and retires|
|Diaby nearing return after near 18-month lay-off|
|Nasri would love to finish career at Manchester City|
|Captain Howedes extends Schalke stay|
|M´Vila keen to stay if Sunderland survive|
|Johnson admits child sex and grooming charges|
|Amazing Mahrez is one of Premier League´s best - Ulloa|
|Ronaldo, Messi rivalry good for football - Zidane|
|Barros Schelotto leaves Palermo|
|Age is just a number - Ilori defends Klopp´s team selection|
|Messi, Suarez and Neymar rested for Copa second leg|
|Madrid can dream of trophies under Zidane - Raul|
|Ancelotti: Italy job is a decade away|
|Reus will become a monster, says Dortmund boss Tuchel|
|Young Tottenham stars don´t know their limits - Lloris|
|Niang happy at Milan despite Leicester interest|
|Ticket price rise means more tourist fans, warns football supporters chairman|
|Ogbonna revels in first West Ham goal|
|Copa Libertadores Review: Huracan, River Plate advance to group stages|
|Klopp backs Benteke to rediscover goalscoring form|
|Turan will not leave Barca for China - agent|
|Beating Chelsea more difficult without Mourinho - Motta|
|Tuchel praises Dortmund for ´perfect game´|
|Klopp rues Liverpool wastefulness in FA Cup loss|
|Allegri: Chelsea rumours unfounded|
|Bilic feels weight of history after Liverpool win|
|Coupe de France Review: Second tier Sochaux stun Ligue 1 Monaco|
|West Ham 2 Liverpool 1 (aet): Ogbonna sinks Klopp´s men in cup thriller|
|Football League Review: Rhodes rescues a point to send Boro top|
|Stuttgart 1 Borussia Dortmund 3: Aubameyang helps Tuchel´s men into last four|
|Kyle Allen blames chaotic Texas A&M culture on Johnny Manziel era|
|Dortmund fans stage protest against ticket prices for Stuttgart game|
|Bayer Leverkusen 1 Werder Bremen 3: 10-man hosts dumped out|
|Ferdinand fears title wilderness for United|
|Carvalho lands new Sporting deal with €45m buy-out clause|
|Ben Arfa out for at least four weeks with hamstring injury|
|Neville´s Valencia woes welcomed by Crespo|
|Ozil key to Arsenal´s title hopes - Rosicky|
|Zika threat could keep Solo from Rio Olympics|
|Blanc pleased to have solved David Luiz matter|
|Atletico midfielder Partey suffers thigh strain|
|Dickov: Leicester title run built to last|
|Guardiola not a menace for our players, says Luis Enrique|
|Mexico v Senegal: Osorio believes in youngsters|
|Celta Vigo v Sevilla: Krohn-Dehli not taking Copa del Rey final for granted|
|Madrid confirm Marcelo shoulder dislocation|
|Injury rules Chiellini out of crucial Juve games|
|Oblak extends Atletico deal|
|Blanc hints PSG could move for Ben Arfa|
|Luis Enrique urges Neymar to cope with off-field distractions|
|Carrick: Manchester United not throwing in towel|
|Neville determined to turn things around at Valencia|
|Guardiola hails Lewandowski professionalism amid Real Madrid and PSG rumours|
|Guardiola wary of ´aggressive´ Bochum|
|Premier League reveals new logo|
|West Ham open Payet contract talks|
|I could leave Barcelona for Guardiola, says Busquets|
|Giggs can be Manchester United´s Guardiola - Robson|
|Zidane has everything to become a great coach - Ancelotti|
|Carragher: Liverpool got it wrong on ticket prices|
|Neymar will be at Barcelona for years, claims director|
|Eder talks up Inter´s Scudetto chances|
|Larsson: Watching Barca is like playing FIFA|
|City recruit Wilkinson hoping to debut in Melbourne derby|
|Allegri will join Chelsea, says former coach|
|Zanetti: No need to compare Maradona and Messi|
|Vardy: I never expected Leicester to top Premier League|
|Capello: Ronaldo has at least three years at the top|
|Klopp hoping for Sturridge revival|
|Bilic wants new contract to keep Payet at West Ham|
|Shelvey can be as good as Cabaye - Sissoko|