King's persistent knee injury restricted him to just four Premier League matches last season but, since Redknapp's arrival at Tottenham the 28-year-old has played in 15 league matches.
Redknapp has encouraged King to focus solely on league matches and use cup and international weekends as time for precious recovery.
Tim Sherwood joins Harry Redknapps Tottenham Hotspur revolution
Redknapp said in the Sun: 'If Ledley plays against Ukraine next Wednesday, there is no way he would be able to play for us the following Saturday.
'I explained that but they have gone and picked him anyway. I can't see it myself, it's mad. It's pointless at best. '
Ledley came into training on Monday after the Chelsea game and his knee was badly swollen. He usually goes straight off to see the medical staff and they get to work on him. He hardly trains with us.
'He barely manages anything on a Friday the day before a game, that's how it has to be with him. '
Ledley is a fantastic player for us and I would never stop any player playing for their country. It's great for them and it's good for Spurs if we have players in the England squad, so I am sympathetic towards him. He has played really well this season.
'But people have to understand the situation and how we have to manage him. He can play Saturday and Saturday, with a bit of work on an exercise bike or a swim in between. He has no cartilage in his knee.'
It is understood that Capello will not consider him for the relatively unimportant friendly against Slovakia. However, with both Rio Ferdinand and John Terry having missed recent matches through injury, Capello would ideally like the back-up option of King for the World Cup qualifier against the Ukraine.
Although currently both fit, Terry and Ferdinand have not played together since the 4-1 win against Croatia last September. Since then Phil Jagielka and Matthew Upson have both deputised, but Capello could not fail to have been impressed when he watched King help Tottenham record clean sheets over the past month in both the Carling Cup final against Manchester United and then the victory against Chelsea.
However, Redknapp believes there would be no chance of King competing in an international tournament, when games are played every four-five days.
'There would be no point in Ledley playing against Slovakia. Why would you do that?,' he said 'You couldn't throw him in to see what he can do because you could not take Ledley to the 2010 World Cup. His knee is not up to it. It'd blow up under the strain.'