Lowe offered that analysis in an interview with Forbes.com.
Clowney was limited to four games his rookie year after being selected first overall in the draft. He suffered a lateral right meniscus tear in the Texans' 2014 season opener.
He had arthroscopic knee surgery the next day and attempted to return to the field in the following month.
Continued swelling in his knee and pain eventually made clear the arthroscopic surgery was not sufficient. Due to articular cartilage damage, Clowney underwent microfracture surgery on Dec. 8.
The second surgery ended his season.
The surgery involves creating tiny fractures in the bones surrounding the knee to increase blood flow to the area and aid the recovery of the cartilage. It also requires a demanding and disciplined rehab schedule.
As part of that rehab, the Texans have used blood flow restriction therapy, which is designed to minimize muscle deficits early in rehab.
According to ESPN's Stephania Bell, the Texans were the first team in the league to implement such training, which is also called "tourniquet" training.
Lowe told Forbes while someone of Clowney's size would typically have lost three or four centimeters of girth around his quadriceps while recovering from this surgery, Clowney has lost only between half a centimeter and one centimeter.
"The real goal in the end is to have him be who he was before he got hurt," Lowe said.