It comes as no surprise that security will be in full force for the 2014 Boston Marathon, but one of the new defense guidelines from the Boston Athletic Association prohibits certain military marchers from treading along the side of the road as they’ve done in years past.

According to Runner’s World, the practice of ruck marching during the Marathon – marching in full fatigues while carrying 40-pound rucksacks for the full 26.2 miles – which has taken place for a decade, does not abide by new security restrictions.

Says the BAA, “units or groups such as military ruck-marchers and cyclists, which have sometimes joined on course, will not be allowed to participate.”

It’s important to note that such reservations are not intended to slight the armed forces in any way. In fact, the BAA told BostInno that 130 National Guardsmen will act as official participants in the race and will march accordingly.

The regulations limit the number of people utilizing the course that may cause a threat to the runners, spectators, and everyone in between. But perhaps most importantly, it abides by the rule that prohibits any bags from being brought along the course and into densely populated areas like that long Bolyston Street.

The two pressure cooker bombs responsible for the unimaginable carnage were thought to have been concealed in standard looking backpacks.

One Boston-based organization, aptly called Tough Ruck, planned to march this year in remembrance of those who fought and died for their country, as well as those killed and injured in last year’s devastating Marathon bombing. For them, not being able to march is a tough pill to swallow but they, perhaps more than anyone, understand the need for impregnable security.

“My first reaction was of course disappointment, but I understand that there are safety and security concerns,” said Stephen Fiola, a member of the National Guard who would have been rucking for the seventh time this year, to Runner’s World. “We knew that there were concerns, but we did not know that a policy was going to come out prior to the B.A.A. announcement.”

Fiola went on to note that some 746 military marchers from 29 states registered to participate along the side of the hilly course. Consider, though, that last year about 20 to 30 brothers in arms trekked from Hopkinton to Boston.

One of those was Carlos Arredondo, the cowboy hat wearing hero who helped rush injured and at risk passersby away from the finish line area on Boylston Street where two pressure cooker bombs combusted, killing three and injuring over 260.

For more information on baggage, gear, spectating, and allowable or prohibited items, check out the BAA’s information here.