Flywheel vs. Nordic Hamstring Curl: Which is Better for Hamstring Strength and Injury Prevention?

Hello Coaches,

Today, we’ll explore two key methods for hamstring strength training and injury prevention: flywheel training and the Nordic Hamstring Curl (NHC). Both focus on eccentric strength, but in different ways. Flywheel workout machines use inertia-based resistance for adaptive eccentric overload, while NHC relies on bodyweight resistance. In this article, we’ll break down the differences, benefits, and practical applications of each method, helping you integrate them into your training programs.

The Importance of Hamstring Training in Sports

Hamstrings are essential for high-speed actions such as sprinting and changing direction, but they are also one of the most injury-prone muscle groups. Studies show that hamstring injuries account for 12% to 16% of all muscle injuries in team sports, with alarmingly high recurrence rates.

To mitigate this risk, eccentric training has proven to be an effective strategy. Both flywheel and Nordic Hamstring Curls target eccentric strength, but they do so in different ways.

Flywheel Training: Adaptive Resistance and Eccentric Overload

Flywheel training uses inertial discs that generate resistance proportional to the force applied by the athlete. This allows for continuous stimulus during both the concentric and eccentric phases of movement.

Key benefits of flywheel training:

1. Load individualization: Resistance is adjustable to the athlete’s capacity, making it ideal for personalized training based on individual needs and levels.
2. Greater eccentric overload: Flywheel training allows for high-intensity eccentric work, promoting unique muscular adaptations.
3. Transfer to sports performance: It enhances skills such as acceleration, deceleration, and horizontal force—key in sports like soccer and rugby.

Limitations of flywheel training:

• It requires specialized equipment, which might not be accessible to all facilities.
• Initial technique needs supervision to prevent injuries.

Nordic Hamstring Curl (NHC): Simplicity with Bodyweight Resistance

The NHC uses bodyweight as resistance, emphasizing the eccentric phase. During the movement, the athlete starts in a kneeling position with the torso straight and lowers themselves toward the ground while activating the hamstrings.

Key benefits of NHC:

1. Simplicity and effectiveness: It requires no additional equipment beyond a partner or an ankle-holding device.
2. Injury reduction: Programs that include NHC have been shown to reduce hamstring injuries by up to 50%.
3. Homogeneous muscle activation: It is particularly effective for engaging both the biceps femoris and semitendinosus.

Limitations of NHC:

• It is an advanced exercise and may be difficult for beginners or weaker athletes.
• Intensity cannot be easily adjusted, which can limit its efficacy in early rehabilitation phases.

Comparative Studies: What Does the Science Say?

1. Eccentric efficiency:
   • Flywheel training generates higher levels of eccentric overload compared to NHC, thanks to its variable and continuous resistance. This allows for a more personalized stimulus.
   • However, the NHC is effective at strengthening critical muscle lengths, especially in the distal portion of the biceps femoris, where injuries often occur.
2. Muscle activation:
   • Electromyographic studies show that NHC tends to produce more uniform activation across the muscle, while flywheel exercises can target specific regions depending on the exercise design.
3. Adaptation and injury prevention:
   • Both methods increase fascicle length and improve eccentric strength, reducing the risk of injuries. However, flywheel training appears to be more effective at increasing fascicle length in shorter periods.
4. Rehabilitation:
   • For athletes returning from injury, flywheel training may be a better option due to its adjustable intensity and reduced initial fatigue. NHC can be introduced later as a progression.

How to Choose Between Flywheel and NHC

Both methods are effective, but their application depends on factors such as the athlete’s level, program objectives, and equipment availability. Here’s a practical guide:

Use Flywheel if:

• You want to customize the load and work with maximum eccentric overload.
• You’re designing a program for advanced athletes or those in rehabilitation.
• You aim to improve specific sports skills such as sprinting and directional changes.

Use NHC if:

• You have limited resources and need a simple, cost-effective option.
• You want to include it in general injury prevention programs.
• You’re working with a large group of athletes and need a standardized, effective method.

Combine both if:

• You want to leverage complementary benefits. For example, use flywheel in the early phases of training or rehabilitation and NHC as a progression to consolidate eccentric strength.

Example of a Combined Program

Warm-Up:

• Joint mobility and glute activation (10 minutes).

Main Session:

1. Flywheel Leg Curl: 3 sets of 6 reps, focusing on the eccentric phase.
2. Flywheel Hip Thrust: 4 sets of 8 reps to improve hip strength.
3. Nordic Hamstring Curl: 3 sets of 5 reps (progressively adding more reps throughout the program).

Cool-Down:

• Static stretches for hamstrings and glutes (10 minutes).

Conclusion

Hamstring training is essential for performance and injury prevention. Both flywheel strength training and NHC offer unique benefits. The key is selecting the right approach based on the athlete’s needs and training goals. Combining flywheel exercises with NHC can maximize eccentric strength and reduce injury risks. Have you tried flywheel resistance training in your programs? Which method do you use more?