Yachts sail past at sunset after government restrictions were eased amid the outbreak of the coronavirus disease (COVID-19), in Pembroke, Malta May 25, 2020. REUTERS/Darrin Zammit Lupi

A member of the Serpentine swimming club trains near a swan in the Serpentine Lake in Hyde Park during a test session prior to its official reopening on Monday, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 17, 2020. REUTERS/Toby Melville TPX IMAGES OF THE DAY

A man is seen on a jet ski in the sea off Brighton as restrictions on watersports have been lifted since the lockdown following the outbreak of the coronavirus disease (COVID-19), Brighton, Britain, May 14, 2020. REUTERS/Toby Melville

A man is seen kayaking on the River Thames in East London as restrictions on watersports have been lifted following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 14, 2020. REUTERS/Steven Watt

People jet ski in the sea off Brighton as restrictions on watersports have been lifted since the lockdown following the outbreak of the coronavirus disease (COVID-19), Brighton, Britain, May 14, 2020. REUTERS/Toby Melville

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath poses during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath poses with his medals during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

REFILE - CORRECTING SPELLING OF SURNAME Team GB Rower Liam Heath during a training session at his home in Guildford, following the outbreak of the coronavirus disease (COVID-19), Guildford, Britain, May 9, 2020. REUTERS/Matthew Childs

Harry Richards and Charlie Harbord attempt to row the length of the River Thames (346km) from their living room to raise money for the NHS, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 7, 2020. REUTERS/Peter Nicholls

Harry Richards and Charlie Harbord attempt to row the length of the River Thames (346km) from their living room to raise money for the NHS, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 7, 2020. REUTERS/Peter Nicholls

Harry Richards and Charlie Harbord attempt to row the length of the River Thames (346km) from their living room to raise money for the NHS, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 7, 2020. REUTERS/Peter Nicholls

Harry Richards and Charlie Harbord attempt to row the length of the River Thames (346km) from their living room to raise money for the NHS, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 7, 2020. REUTERS/Peter Nicholls

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno with his dad Robert and Mum Deborah, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno with his dad Robert, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly with his dog Baxter during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno with his dad Robert and Mum Deborah, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith TPX IMAGES OF THE DAY

Team GB Diver James Heatly poses after a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly with his dog Baxter during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB Diver James Heatly with his dog Baxter during a training session at his home in Balerno, following the outbreak of the coronavirus disease (COVID-19), Balerno, Scotland, Britain, May 7, 2020. REUTERS/Lee Smith

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs TPX IMAGES OF THE DAY

Team GB canoeist Mallory Franklin during a training session at her home in Cheshunt, following the outbreak of the coronavirus disease (COVID-19), Cheshunt, Britain, May 7, 2020. REUTERS/Matthew Childs

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic carry boat during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic carry a boat after the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen rowing during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic push boat from shore as they start with the training at Zagreb's lake Jarun after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

Brothers Valent and Martin Sinkovic are seen resting during the training after the relaxation of the coronavirus disease (COVID-19) restrictions, in Zagreb's lake Jarun, Croatia, May 4, 2020. Picture taken May 4, 2020. REUTERS/Antonio Bronic

A general view of Iman Avdic's small plastic pool inside an improvised greenhouse in her grandfather's orchard in Doboj, Bosnia and Herzegovina April 23, 2020. Picture taken April 23, 2020. REUTERS/Dado Ruvic

Iman Avdic's father and coach Evelin Avdic, trains the national multiple swimming record holder, who maintains her form by practicing in a small plastic pool inside an improvised greenhouse in her grandfather's orchard in Doboj, Bosnia and Herzegovina April 23, 2020. Picture taken April 23, 2020. REUTERS/Dado Ruvic

Iman Avdic's father and coach Evelin Avdic, trains the national multiple swimming record holder, who maintains her form by practicing in a small plastic pool inside an improvised greenhouse in her grandfather's orchard in Doboj, Bosnia and Herzegovina April 23, 2020. Picture taken April 23, 2020. REUTERS/Dado Ruvic