Lindsey Grundfast became the head coach of the women's lacrosse program during the fall of 2021.

The 2023 season saw Grundfast's team set several single-season records including caused turnovers (169), draw controls (209), ground balls (374), assists (54), points (207), and goals (153). Furthermore, the 2023 season saw one of Grundfast's student-athletes land Second Team All-OAC which marked the first time in program history a Muskingum Women's Lacrosse student-athlete earned All-OAC honors in back-to-back seasons.

Along with numerous team records, Grundfast guided players into the Muskingum record books as individuals. During the 2023 campaign, Muskingum players set individual single-season records including most goals, most caused turnovers, most assists, and  most ground balls.

During the 2022 campaign, Grundfast's student-athletes left their mark in the record books. Players reached top ten marks in goals, assists, draw controls, and groundballs for a single season. Additonally, under Grundfast, two student-athletes earned All-OAC accolades for their outstanding play.  The 2022 season marked the first time in program history the Muskies have had a player receive All-OAC Second Team honors, and the first time Muskingum has had two student-athletes earn All-OAC accolades in the same season.

Grundfast arrives at Muskingum after serving three years as the head coach of the Earlham College women's lacrosse program. During her time with Earlham, Grundfast led a turnaround of the Quaker program that saw her lead the 2019 team to a second-place finish in the Heartland Collegiate Lacrosse Conference (HCLC) and a first-ever berth in the HCLC Tournament as the two-seed. The Quakers finished the season with an 11-6 overall mark and a 5-1 slate in the HCLC. Seven players were recognized with All-HCLC honors, including first-year Claudette Roskamp, who was also tabbed as the league's Offensive Player of the Year and Newcomer of the Year. Roskamp finished the season ranked 15th among NCAA Division III leaders in total goals (83) and 14th in goals per game (4.88).

During the shortened 2020 season, Grundfast led Earlham to a 4-1 record, outscoring opponents 64-40, until the season ended abruptly due to COVID-19. Earlham did not compete during the 2021 season.

Academically, the Quakers have excelled in the classroom under Grundfast's leadership. The program has maintained a cumulative team GPA of 3.4 and earned individual and team academic awards from the Intercollegiate Women's Lacrosse Coaches Association (IWLCA).

During her three-year tenure as Earlham's head coach, Grundfast was named Senior Woman Administrator for the Quaker athletic department. Additionally, she was involved in various Earlham organizations outside of athletics. Grundfast served as a staff representative for a two-week pre-orientation program for incoming first-year students and served as a faculty leader with Earlham's outdoor education program. She taught a team-building class for athletics and wellness. Furthermore, Grundfast collaborated with student-athletes to create the Queer Athlete & Allies Collective group (QAAC), which serves as a safe space for LGBQT+ student-athletes. She was awarded the Lavender Faculty/Staff Ally Award for her work with QAAC.

Before being the head coach for the Quakers, Grundfast served as an assistant coach for Earlham and helped establish the first-year program and mentor two all-league selections.

Before starting her coaching tenure at Earlham, Grundfast was the goalkeeper coach for the girls lacrosse team at Pinkerton Academy (Derry, N.H.) and head coach and clinic director for the NH Tomahawks for two seasons. At Pinkerton, she helped lead the program to the 2016 New Hampshire Division I state championship.

Grundfast also spent a season as the assistant coach at NCAA Division III State University of New York, New Paltz. She assisted the head coach with managing and planned daily practices and prepped for intercollegiate contests.

As a student-athlete, Grundfast started all four years for the Dominican College women's lacrosse program as a goalie. She ranked among the top 10 in the nation in saves per game in 2008 and 2009. Grundfast was a three-year captain for the squad and ranks first in career saves (629) for the Chargers and second in career saves per game (12.84).

Grundfast graduated from Dominican in 2010 with a B.A. in mathematics. She completed her Master of Science in education from the State University of New York at New Paltz in 2012.