NEW DELHI, India - Alternating circuits and team personnel could be the way forward for Formula 1 to add new races to a crowded calendar without losing existing ones.Speaking at the Indian Grand Prix, some team bosses suggested commercial supremo Bernie Ecclestone might not have to wield the axe to keep the calendar manageable.Next year has 20 races, although a question mark still hangs over Bahrain, with a new US Grand Prix in Austin, Texas, scheduled.New Jersey announced last week that they had agreed a 10-year deal with Formula One supremo Bernie Ecclestone from 2013 and Russia's Sochi resort on the Black Sea has been handed a 2014 date.BUSY SCHEDULEFrance still dreams of regaining its slot although progress is hard to detect.Renault's team boss Eric Boullier said a possible alternation with Belgium would allow new races to come in without killing off French hopes.Boullier said: "There is a slot to take because we are talking about alternating with another European grand prix so it doesn't affect too much the number of races."I think some European Grands Prix can afford one race every two years rather than a race every year. So this could be a good way of keeping different track locations in Europe," he said.Germany's two races already alternate while Spain currently has two Grands Prix a year.Teams are reluctant to go to more than 20 races because of the strain that puts on mechanics, technicians and engineers - unless they receive more money to pay for more staff.TEAMS TAKING STRAINWith a cost restriction agreement in place, and no testing during the season, teams have shed their test teams and are limited to how many they can take to a race.McLaren's Martin Whitmarsh said: "I think 20 races and a lot of flyaways (long-haul races) is pretty hard on the team and I think we are at tipping point."You are getting close to the point where you do need to alternate (staff). It's the NASCAR approach where you alternate crews. By the time the guys get back and strip down (the cars) after Brazil it will be December. By January those same guys will be building the car, during February they are going to be testing the car and then they are into a flog around the world," said Whitmarsh.Whitmarsh questioned how much pressure the calendar would be under ultimately, however."I've heard about the second US Grand Prix, I've heard about Russia but at the same time there's always some question marks being raised about others," he said.Ecclestone has expressed unhappiness about South Korea's handling of their race while Bahrain remains a doubt and Austin's circuit is still under construction.Ecclestone said: "We seem to be a little bit away from the time when there's massively in excess of 20 circuits. If we have that great problem then we'll find a way to deal with it," said Whitmarsh.