ENGLEWOOD, Colo. -- Players from four NFL teams will not formally report to their respective team facilities next week to begin voluntary offseason workouts, the teams said in statements released by the NFL Players Association.

The Denver Broncos, Seattle Seahawks and Tampa Bay Buccaneers on Tuesday announced their intentions to skip the workouts, while the Detroit Lions joined them in making the decision on Wednesday.

In their statement, the Broncos players cited rising COVID-19 positivity rates in Denver and surrounding communities, as well as the lack of "adequate protocols in place." Sources told ESPN that the players voted to take this action and notified coach Vic Fangio earlier Tuesday morning that the vote had taken place.

The Seahawks players issued a similar statement in which they noted, "The NFLPA has provided us with thorough research and information regarding our safety as players as we enter voluntary workouts this year, especially the benefits on our health and safety from a virtual off-season last year. After considering all the facts, we as a team have decided to make a decision that is uncomfortable but necessary."

The Super Bowl champion Bucs said they "held each other accountable to do the work it took to win" during last year's virtual offseason and "we plan to do that again."

Offseason programs are scheduled to begin April 19 leaguewide, at which point daily testing for players and staff will commence, according to a memo sent to teams on March 31. Players who are currently using the weight room at team facilities or being treated by club medical staff have to be tested, at minimum, every other day. Teams can test more if they wish, but that is the minimum requirement.

Seahawks wide receiver Tyler Lockett said Tuesday it was "easy" to learn what coaches were teaching in a virtual setting last offseason.

"When we went back into camp, things were amazing," he said. "Everybody was flying around. You would have thought that we never missed a practice or we never missed an OTA. That's the beauty of it, that we're able to see that it's all mental, so for us, when we went through that virtual experience, we had to be on our P's and Q's, because we wanted to make sure that we were all great when we went back out there, and I think the NFL season just kind of showed that we were still on it."

Lockett considered opting out of the 2020 season because of COVID-19 concerns before deciding to play. Seattle did not have a single player contract the virus last season.

The Seahawks do have a new coordinator this year in Shane Waldron, who is expected to change some if not most of their offense. But the Seattle players' decision to not take part in voluntary workouts won't be as financially costly as it would be for players on teams, such as the Green Bay Packers, that put offseason workout bonuses into their contracts. Those bonuses are tied to participation in offseason workouts. The Seahawks do not include them in their contracts, although safety Quandre Diggs has a $100,000 workout bonus in his. The Seahawks acquired Diggs and his contract in a 2019 trade with the Detroit Lions. He's the only Seahawks player whose contract includes a workout bonus, according to Roster Management System.

In their statement, the Broncos' players said that "COVID-19 remains a serious threat to our families and our communities, and it makes no sense for us as players to put ourselves at risk during this dead period.

"Positivity rates in our city are higher than they were at this time last year and we know players have been infected at club facilities in recent weeks. Despite having a completely virtual offseason last year, the quality of play across the NFL was better than ever by almost every measure."

Kicker Brandon McManus is the Broncos' player representative in the NFLPA and has been vocal over the past year regarding the need for consistent health and safety protocols.

Voluntary workouts are held Monday through Thursday, with Friday through Sunday as days off. Many players leave the area for the weekend, including those who don't live in the Denver area in the offseason. So how the players would be tested and on what days when they return to the facility for the next week of workouts is a subject that some players say they want clarified.

Some Broncos have been in the team's facility in recent weeks, including players who are recovering from injuries or offseason surgeries. Coaches, trainers and other team personnel have been working in the building under certain guidelines, including wearing facial coverings.

The Broncos organization did not respond to requests for comment regarding the players' statement on not attending voluntary workouts.

Vaccinations are increasing in the Denver area, with all individuals 16 years or older eligible to receive the vaccine. Positivity rates released Tuesday for Arapahoe County, where the Broncos' complex is located, was 5.6%.

Players from the Lions, in a statement released by the NFLPA, said "it is in everyone's best interests to play it safe again this season" after "no acceptable resolution to our union's negotiations with the NFL over comprehensive COVID-19 protocols."

Tampa Bay's players said they made a commitment "to the organization, to Bucs fans and to each other" to defend its Super Bowl title, but "in light of the ongoing pandemic, we are choosing to take a stand with other players across the league and exercise our right to not participate" in the voluntary offseason program.

The NFL sent a memo to teams Tuesday that said Tier 1 or Tier 2 personnel will be required to be vaccinated in order to work in the team facilities, unless they must abstain for health or religious reasons.

ESPN's Brady Henderson contributed to this report.