Broad has been forced to miss a number of games due to a long-standing knee injury, and Newell believes that England's T20 captain must begin to prioritise Test and one-day international cricket.
"Stuart is a key man for Test cricket and one-day internationals, so in terms of managing his fitness I think we are going to have to look at Twenty20 for Stuart," Newell, who is also an England selector, told reporters.
"The last two or three years he has picked up a lot of little things and he would want to have played more cricket than he has.
"There is a lot of ODI cricket coming up and how you manage the workload for players like Stuart through the summer and as you prepare for the 50-over World Cup next February is something that will have to be looked at."
Broad made his return from injury for Nottinghamshire against Durham earlier this week.