Periodization for Hybrid Athlete

How to Structure Strength and Endurance Training for Maximum Adaptation

For athletes chasing both strength and endurance, programming becomes a balancing act. Should you run before lifting? Alternate days? Focus on one quality at a time? The answer depends on your goals — and on smart periodization.

In this post, we break down what the latest science says about combining strength and endurance training, how to avoid the classic interference effect, and which training structures actually work for hybrid athletes.

What Is Concurrent Training?

Concurrent training refers to combining resistance (strength) and endurance training within the same program. It’s a common strategy in sports like CrossFit, MMA, military prep, and motorsports — and increasingly popular among athletes seeking all-around performance.

The challenge is that the endurance and strength adaptations are driven by different — and sometimes competing — physiological pathways.

The Interference Effect

The “interference effect” refers to a phenomenon where endurance training blunts the adaptations of strength or muscle hypertrophy, particularly when both are trained intensely and close together.

This effect was first documented in a classic 1980 study by Hickson, who found that athletes training both strength and endurance improved less in maximal strength than those training strength alone.

More recent research has refined this idea. Key takeaways:

1. The interference effect is more noticeable in lower body hypertrophy and strength (because you use them mainly in running and cycling).

2. High-volume or high-intensity endurance (like HIIT or long runs) has a stronger negative influence compared to low-intensity endurance work.

3. The timing and sequencing of sessions play a major role.

What the Science Says About Periodization?

Recent studies have compared different ways of sequencing strength and endurance training:

1. Block Periodization

Example: 3 weeks of running → 3 weeks of strength training.

Finding: The first block tends to show the largest adaptation.

Implication: Want to peak in strength? Do the strength block first.

(Mikkola et al. (2012) – “Effect of sequencing strength and endurance training on neuromuscular and endurance performance”)

2. Same-Day Training (AM/PM)

Example: Strength in the morning, endurance in the evening.

Finding: Comparable results to alternating days — if sessions are separated by ~6+ hours.

Implication: Still a viable strategy, especially for busy athletes. If you don't have the time, prefer training strength and endurance on separate days, or if done within the same session, start with strength first.

(Jones et al. (2013) – “Concurrent training: a meta-analysis”)

3. Alternating Days (most effective)

Strength and endurance are trained on separate days.

Pros: Reduces fatigue and interference. Easier recovery.

Cons: Requires more training days per week.

Best Practices for Hybrid Athletes

Goal	Recommendation
Maximize strength	Consider block periodization. Avoid long aerobic sessions on strength days. Keep endurance mainly moderate volume Z2 in the strength block with few shorter high intensity sessions per month.
Maximize endurance	Endurance before strength. Prioritize zone 2 and tempo work. Use strength as support. Keep strength training on maintenance level, avoid excess DOMS (soreness).
Improve both	Separate sessions by 6–8 hours (e.g., morning/evening). Alternate days when possible. Don't push over the limit in either, or the interference effect will start influencing the other.

Key Takeaways

Concurrent training works within reasonable limits. It's important to understand that running a sub-11-second 100m and a sub-2.5-hour marathon are not achievable, but going sub-12 seconds and 3 hours may be possible for some people. But even then, going to extremes isn't something you may need or want, so choose your goals and train accordingly. And remember, all these results depend on smart planning.

To avoid interference, pay attention to:

• Order of training

• Recovery time between sessions

• Volume and intensity of endurance work

Periodizing your training — even in simple blocks — can improve long-term gains.

Hybrid athletes need to master both sides of the spectrum. With strategic periodization, you don’t have to sacrifice one for the other. Instead, you can sequence your training for synergy — not conflict.