Off-Season Strength Training for Endurance Athletes

Tips to Build Strength, Resilience, and Speed

By Jennifer Kurtz, PhD

INTRODUCTION

For endurance athletes, the off-season presents a prime opportunity to work on something that can significantly improve performance and reduce injury risk: strength training.

While logging miles and cardio work remain essential, a targeted off-season strength training program can help you build a foundation that enhances your endurance, power, and resilience for the upcoming race season.

Here’s a guide to incorporating strength training into your off-season with tips and science-backed strategies to optimize your training.

COMPOUND MOVEMENTS: POWER, EFFICIENCY, INJURY PREVENTION

Compound movements – like squats, deadlifts, lunges, and pull-ups – are multi-joint exercises that recruit multiple muscle groups. These exercises are crucial for endurance athletes because they enhance muscle strength and coordination, both of which translate into improved efficiency and reduced injury risk on the road or trail. Compound exercises also help improve core stability, which is essential for maintaining good form during long endurance efforts (Rønnestad et al., 2015).

Resistance training, particularly with compound movements, improves neuromuscular efficiency and maximal strength, both of which are critical for endurance performance (Aagaard & Andersen, 2010). Additionally, incorporating these exercises into training has been linked to enhanced running and cycling economy by reducing the oxygen cost of sustained effort (Berryman et al., 2018). Squats and deadlifts are also effective for developing posterior chain strength, which is critical for propulsive force in running and cycling (Blagrove et al., 2018).

Furthermore, compound movements improve functional strength and promote better muscle activation patterns, reducing the likelihood of overuse injuries caused by biomechanical inefficiencies (Yamamoto et al., 2008). These benefits are especially pronounced when strength training is integrated into the off-season or base training phases, as it complements aerobic development while mitigating injury risk (Laursen & Jenkins, 2002).

Example Routine

• Squats: 3 sets of 8–10 reps
• Deadlifts: 3 sets of 8 reps
• Pull-Ups: 3 sets of 6–8 reps (or as many as possible)
• Lunges: 3 sets of 10 reps per leg

FUNCTIONAL MOVEMENTS: INJURY PREVENTION

Endurance athletes often experience repetitive stress injuries due to high mileage and prolonged periods of similar movements. By incorporating functional, multi-directional strength exercises into your off-season routine, you can strengthen the stabilizing muscles around key joints like the hips, knees, and ankles. This can improve movement efficiency and balance, reducing the likelihood of injuries (Blagrove et al., 2018).

Strength training enhances neuromuscular coordination, which is essential for maintaining proper biomechanics under fatigue (Yamamoto et al., 2008). Furthermore, the inclusion of eccentric exercises targeting the lower body has been shown to mitigate the risk of overuse injuries by improving tendon stiffness and resilience (LaStayo et al., 2003). Balanced muscular strength can enhance running and cycling economy, allowing athletes to sustain endurance performance with less metabolic cost (Joyner and Coyle, 2008).

Additionally, addressing asymmetries through functional strength exercises can correct imbalances that contribute to poor movement patterns, which are a known risk factor for injuries in endurance athletes (Fokkema et al., 2020). These benefits underscore the importance of integrating strength training as a complementary component of an endurance athlete's overall training plan.

Recommended Exercises

• Single-Leg Deadlifts: Improve hip stability and balance.
• Lateral Lunges: Strengthen muscles in the frontal plane, which helps prevent injuries from lateral instability.
• Step-Ups with Dumbbells: Mimics the movement patterns of running while strengthening the glutes and core.

PERIODIZATION: BUILD GRADUALLY

Periodization is the practice of dividing training into distinct phases, allowing athletes to build foundational strength, progress into more intense work, and taper when necessary.

During the off-season, endurance athletes can start with a “base” phase focused on lighter weights and higher reps to build muscular endurance, then progress to heavier, lower-rep strength work, which promotes muscle power and resilience (Rønnestad et al., 2014). This phased approach allows for optimal adaptation while preventing overtraining and fatigue. Additionally, periodized strength training has been shown to improve both aerobic and anaerobic performance, as it allows athletes to build strength without compromising endurance (Schoenfeld, 2010).

Periodization enhances recovery by balancing workload and recovery time, preventing plateauing in performance while reducing the risk of injury due to overuse or insufficient recovery (Issurin, 2010). For endurance athletes, integrating strength work into a periodized plan not only builds power but also reduces the incidence of muscle damage during high-intensity efforts, improving overall performance (Stone et al., 2007). Moreover, periodized strength training programs have been found to increase running economy, particularly when focusing on maximal strength during the off-season, thus helping athletes to sustain their performance during long endurance events (Berryman et al., 2018).

Sample Periodization Plan

This gradual progression minimizes the risk of injury and helps maintain motivation as you build strength throughout the off-season.

• Weeks 1-4: Base Phase — 2–3 sets of 12–15 reps at light weight
• Weeks 5-8: Strength Phase — 3–4 sets of 8–10 reps at moderate weight
• Weeks 9-12: Power Phase — 3 sets of 4–6 reps at heavy weight (focus on explosive movements)

PLYOMETRICS: PRIME THE EXPLOSION

Plyometrics, or jump training, is valuable for endurance athletes because it enhances explosive strength and muscle-tendon elasticity. This type of training helps improve the rate of force production, which is crucial for more powerful strides and greater running economy (Balsalobre-Fernández et al., 2016). Plyometrics can be integrated into the end of a strength session or on separate days, depending on your training split.

Effective Plyometric Exercises

Focus on maintaining good form and landing softly to minimize impact on the joints.

• Box Jumps: 3 sets of 6 reps
• Bounding: 3 sets of 10 bounds per leg
• Lateral Bounds: 3 sets of 8 bounds per side

CORE STRENGTH: STABILITY + EFFICIENCY

Core strength is often the “missing link” for endurance athletes. A strong core improves stability, posture, and overall efficiency in running, cycling, and swimming.

The core is not limited to just your stomach; it also includes your back. The "muscular core" refers to a group of muscles that stabilize and support the spine, pelvis, and torso. These muscles include the rectus abdominis (your "six-pack" muscles), transverse abdominis (deep abdominal muscles), obliques (side abdominal muscles), erector spinae (a group of muscles running along your spine), and even deeper stabilizing muscles like the multifidus and pelvic floor muscles. Together, they work to provide stability, balance, and power for movement and posture.

Core exercises should target all major muscles, including the obliques, rectus abdominis, transverse abdominis, and lower back muscles. Research suggests that core stability reduces “wasted” energy and improves balance, which directly supports endurance performance (Sato & Mokha, 2009). Core-focused training can enhance proprioception, posture, and coordination, all of which are critical for maintaining endurance performance over extended periods.

Core Strengthening Routine

• Side planks with dips: 3 sets, 30–60 seconds each
• Plank with knee drive: 3 sets of 12 reps
• Dead bugs: 3 sets of 8-10 
• Stability ball “stir the pot”: 3 sets of 12 reps
• Stability ball “stir the pot”: 3 sets of 12 reps

RECOVERY: SCHEDULE SPACE TO PREVENT BURNOUT

Incorporating strength training in the off-season can increase muscular strength without compromising aerobic endurance, but that’s only true if sufficient recovery is incorporated into the training plan (Aagaard & Andersen, 2010). This is especially true if strength training is new to your routine – it adds more strain on the body and requires ample recovery time. The combination of proper sleep, nutrition, and recovery strategies ensures that the body can adapt effectively to the increased workload, ultimately improving endurance performance during high-intensity efforts and long-duration events (Mujika & Padilla, 2003).

For endurance athletes, strength training 2–4 times per week during the off-season is usually sufficient, with rest days in between. Sleep and nutrition are critical for recovery and maximizing the benefits of strength work (Knuiman et al., 2018). Sleep plays a crucial role in muscle recovery, as it enhances protein synthesis, reduces muscle soreness, and improves neuromuscular function, which are all vital for optimizing strength adaptations (Reilly & Edwards, 2007).

Additionally, nutrient timing – particularly the consumption of protein and carbohydrates post-workout – has been shown to accelerate muscle repair and glycogen replenishment, thus supporting both strength gains and endurance performance (Ivy, 2004).

Sample Weekly Off-Season Strength Training Routine

Monday: Strength Training (compound exercises, moderate weight)

Tuesday: Endurance Training (easy run or cycle)

Wednesday: Core and Functional Movements (single-leg exercises, planks, lateral lunges)

Thursday: Rest or Light Cross-Training

Friday: Strength Training (heavier weights, focus on lower body)

Saturday: Plyometric Training (box jumps, bounding)

Sunday: Long, low-intensity endurance workout

CONCLUSION 

Incorporating strength training into an endurance athlete's off-season routine provides numerous benefits that extend well beyond improving muscle strength. By focusing on compound movements and functional exercises, athletes can reduce their risk of injury, enhance muscle coordination, and improve overall movement efficiency.

Strength training during the off-season also promotes core stability, which is crucial for maintaining good form and conserving energy during long-duration events. This, in turn, supports better performance, as athletes experience fewer biomechanical inefficiencies and greater neuromuscular control (Sato & Mokha, 2009).

Furthermore, a periodized approach to strength training ensures that athletes can progressively build strength while avoiding overtraining, leading to improved endurance performance when race season returns.

With a well-rounded off-season strategy that includes strength training with adequate recovery and nutrition, endurance athletes can emerge stronger, more resilient, and better equipped to handle the demands of their sport. By focusing on compound movements, core stability, plyometrics, and a progressive approach, you can gain a competitive edge while reducing your injury risk.

The off-season is the ideal time for endurance athletes to integrate strength training that builds resilience, corrects muscular imbalances, and lays a foundation for the upcoming season. Consistent, well-rounded training in the off-season pays dividends when it’s time to race.

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References

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Balsalobre-Fernández, C., Tejero-González, C. M., & del Campo-Vecino, J. (2016). The concurrent validity and reliability of a low-cost, high-speed camera-based method for measuring the flight time of vertical jumps. Journal of Strength and Conditioning Research, 30(7), 2065-2072.

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