Blog Sports

Research Exposes What Puts College Football Players at Risk for Hamstring Strains

Hamstring strains are common among male college American football players. Researchers have been investigating potential risk factors to better understand and prevent these injuries, and they believe they have identified three that all coaches should track.

Hamstring strain injuries can significantly impact performance and sideline players during practices and games. A study titled ​“Risk Factors for Hamstring Strain Injury in Male College American Football Players: A Preliminary Prospective Cohort Study” aimed to identify some of the risk factors that are the root cause of this type of injury.

Researchers at the University of Tokyo Sports Science Institute enrolled 78 male college football players, all in skill positions, during a preseason medical assessment. 

During the study period, 25 out of the 78 participants (32.1%) experienced a hamstring strain. The study highlights three critical risk factors for these injuries, including:

  • Hamstring Flexibility: Injured players had significantly lower hamstring flexibility compared to uninjured players (p = 0.02). This suggests that maintaining good hamstring flexibility may reduce the risk of HSI.
  • Hamstring-to-Quadriceps Strength Ratio (H/Q): The H/Q ratio was significantly lower in injured players (p = 0.047). A balanced strength ratio between these muscle groups is crucial for preventing HSIs.
  • General Joint Laxity: Injured players exhibited lower general joint laxity scores, particularly in the total (p = 0.04), hip (p = 0.007), and elbow (p = 0.04) regions. Reduced joint laxity may contribute to HSI risk.

Pinpoint the Perfect Metrics for Decreasing Injury Risks in Football

Hamstring Exercises Decrease Strain Risks

Below are strategies and exercises address each of these factors and help prevent hamstring strains.

Hamstring Flexibility:

In running sports, the goal of enhancing hamstring flexibility is to reduce the risk of muscle tears or strains and to improve running efficiency, agility, and speed.

  • Warm-Up: Encourage athletes to perform dynamic warm-up exercises before training or competition. Dynamic stretching helps improve muscle flexibility and prepares the body for intense activity.
  • Static Stretching: Include static hamstring stretches after the warm-up. Hold each stretch for 20 – 30 seconds to enhance flexibility. 
  • Foam Rolling: Foam rolling the hamstrings can help reduce muscle tension and improve flexibility. 
  • Regular Mobility Work: Incorporate mobility drills that target the hip and hamstring muscles. These can include leg swings, hip circles, and lunges.
an American football player with a gps tracker for football has a hamstring injury that is looked at by a trainer.

H/Q Ratio (Hamstring-to-Quadriceps Strength Ratio):

The Hamstring-to-Quadriceps Strength Ratio is a calculation in which the strength (peak torque) of the hamstring muscles in eccentric motion is divided by the strength of the quadriceps in a concentric motion. Here’s what researchers say can be done to attain a good ratio:

  • Aim for a balanced strength ratio between the quadriceps and hamstrings. A ratio of 3:2 (quadriceps to hamstring strength) is recommended to decrease the risk of injury.
  • Include hamstring-specific exercises in strength programs. Some effective exercises include Romanian deadlifts, glute-ham raises, and Nordic hamstring curls.
  • Strengthen supporting muscle groups such as the gluteus maximus and calf muscles. These muscles assist the hamstrings during movement patterns like running and sprinting.

General Joint Laxity:

Joint laxity refers to increased flexibility or looseness in the joints. While some degree of joint mobility is normal, excessive laxity can increase injury risk.

  • Strengthen Stabilizing Muscles: Focus on strengthening the muscles around the joints (e.g., hip stabilizers, core muscles). This helps stabilize the joints and reduces the strain on the hamstrings.
  • Proprioceptive Training: Incorporate balance and proprioceptive exercises to improve joint stability. Examples include single-leg balance exercises and stability ball drills.
  • Avoid Overstretching: While flexibility is essential, avoid excessive stretching that may compromise joint stability. Emphasize controlled movements during stretching routines.

By addressing these factors, coaches, players, and medical staff can work together to minimize the occurrence of this type of injury and keep athletes on the field. Researchers say future studies should explore interventions to optimize hamstring flexibility, strengthen muscle groups, and maintain joint health.

Using Data For Load Management in Football is Easier Than You Think

GPS Football Trackers for Hamstring Injury Prevention

GPS football trackers help coaches prevent injuries by providing live and post session data on players to help manage workloads.

And now it’s easier than ever to do it because KINEXON PERFORM GPS is the first athlete monitoring system for outdoor sports to offer a fully automated workload.

American football players are now being equipped with player trackers that provide coaches and sports data analysts with vital information that helps prevent injuries in football.

It’s completely wireless, and there is no waiting for your data to upload or download. Plus, you can access it from anywhere at any time.

If you’d like to learn more about it, feel free to reach out to us. Or download the brochure by clicking the link below.

Start Using The World's First Athlete Monitoring System With a Fully-Automated Workflow

More stories

How Basketball Performance Data Connects the Court and Weight Room

What happens on the court shapes what athletes need in the weight room. Purdue’s Jason Kabo shares how he cross-references KINEXON performance data with sprint testing and other measures to adjust training, manage individual workloads, and guide daily decisions.

From Jump Count to a More Complete View of Volleyball Load

Jump count is one of the most familiar metrics in volleyball, but it only captures part of an athlete’s physical performance. Looking at movement intensity, like acceleration or changes of direction, and position-specific demands can provide the context needed for a more complete view of the overall load.

Limited Camps, High Demands: Preparing for International Handball Tournaments

The Women’s EHF EURO and Men’s World Championship present a similar challenge for performance staff: preparing players for an intense tournament with limited time together. How can national teams use the camps leading into competition to better understand and manage individual load?

How Drill Intensity Shapes Weekly Basketball Load Targets

Basketball coaches need more than a list of practice drills. Historical performance data and drill intensity help coaches refine practice plans, manage individual workloads and adjust the next session based on what athletes actually completed.

Sustainability: Can the Athlete Maintain Intensity Throughout the Duration of the Game?

Matching game workloads are only part of athlete preparation. Can players sustain high-intensity efforts when fatigue builds? Read more from Dayannara Munoz, KINEXON Sports Customer Success Manager, about how performance data helps coaches assess changes in output, compare practice with competition, and prepare athletes to meet the demands of the entire game.

How Individualized Football Performance Data Improves Load Management

Football performance data helps coaches move beyond team averages to individualize load management. By combining GPS metrics with each athlete’s role, historical data, and readiness, coaches can identify the right exposure, reduce excessive stress, guide recovery, and better prepare every player for game day.

Beyond the National Team Window: How the DHB Connects Performance Data

National teams spend only a fraction of the season with their athletes. See how the German Handball Federation connects club and national-team data to maintain performance context across the season and support individual decisions when players move between environments.

One Athlete, Two Jerseys: Connecting Athlete Monitoring Between Club and Country

When athletes move between club and country, their performance history moves with them. The 2026 FIBA Women’s Basketball World Cup highlights why monitoring continuity matters when athletes arrive with different workloads, competition exposure and preparation behind them. 

The Role of Connected Ball Technology in Modern Officiating

From ghost goals to offsides, officiating technology has steadily raised fairness in football. But the one element at the center of every decision, the ball, has until now been silent. Connected Ball Technology (CBT) changes that, giving football’s most iconic object its own voice.

COMPETE Vision on a New Level: Refined for Faster Insights

The latest COMPETE Vision update streamlines the entire performance analysis workflow, from camera setup to automated reporting. Faster uploads, improved player identification, automated court calibration, and smarter player assignment help coaches spend less time managing technology and more time turning objective data into coaching decisions. 

How KINEXON Game Insights Gives Basketball Coaches the Tactical Advantage

Basketball coaches already use in-game tracking data to evaluate their athlete’s physical exposure. As more teams adopt performance tracking methodologies, that same underlying data source can extend beyond physical optimization and be utilized to compare rosters, assess opponents, and understand the demands behind each matchup.

From Data to Decisions: Six Key Takeaways from Elite Handball Performance Practitioners

Elite handball is one of the most physically demanding team sports in the world. Within sixty minutes, players sprint, decelerate, jump, throw, change direction, absorb contact, and repeat those actions under fatigue, all while making split-second tactical decisions. 

From Potential to Performance: How AI, Ball & Player Tracking Are Transforming Talent Identification in Youth Football

How can AI, player and ball tracking, and expert scouting work together to identify football talent? Discover how Skillers Academy, SAP, and KINEXON Sports combine connected technologies and human expertise to create a more objective and accessible approach to youth talent identification.

How Xavier Women’s Basketball Optimizes Daily Load Targets for Low- and High-Minute Players

Optimizing daily workloads goes beyond keeping players fresh. For Xavier’s Gil Weinstein, Head Strength and Conditioning Coach, daily (and weekly) performance reports helped connect practice loads to game demands, guide workload adjustments, and support 99% player availability throughout the 2025 – 26 season. 

Inside Columbia Women’s Basketball’s Approach to In-Season Load Management

Managing in-season workloads takes more than tracking minutes. Performance data helps basketball coaches individualize weekly targets, adjust practice plans, and keep high-minute players, role players, and scout team athletes prepared to perform.