Programming Endurance & Strength Training

A Guide for S&C Coaches

For Strength and Conditioning (S&C) coaches, designing programmes that integrate both endurance and strength training is a nuanced challenge. These two forms of exercise often have conflicting demands, yet both are essential for many athletes seeking peak performance. Endurance training is critical for improving cardiovascular fitness, aerobic capacity, and time to exhaustion, while strength training enhances muscular power, force production, and overall durability.

However, when combined, endurance and strength training can interfere with each other’s adaptations. This phenomenon, known as the “interference effect,” has long been a concern for S&C coaches. Add to this the logistical complexities of timing sessions, managing fatigue, and addressing the unique needs of individual clients, and it becomes clear why programming concurrent training is such a complex task.

Recent research by Vikestad and Dalen (2024) offers insights into one key aspect of concurrent training: the sequence of endurance and strength sessions. By comparing the effects of Endurance-Resistance (ER) and Resistance-Endurance (RE) training on endurance performance, their work provides valuable guidance for coaches seeking to optimise results.

The Challenges of Combining Endurance and Strength Training

Programming concurrent endurance and strength training poses a host of challenges for S&C coaches. Chief among these is the interference effect, where endurance training can blunt strength adaptations, particularly in hypertrophy and power development. This effect arises due to competing molecular pathways activated during these training modes, which can inhibit the body’s ability to adapt fully to either.

Fatigue management is another major issue. Strength training induces muscle damage and depletes glycogen stores, potentially impairing performance in subsequent endurance sessions. Similarly, a taxing endurance workout can leave an athlete too fatigued to perform heavy lifts with proper form or intensity.

Time constraints often complicate programming further. Athletes and recreational clients alike may lack the ability to separate endurance and strength sessions by the recommended six or more hours. This forces S&C coaches to decide whether to prioritise one training mode over the other or find creative solutions to integrate them.

Finally, programming must account for individual variability. The goals, fitness levels, and recovery capacities of clients differ widely, requiring tailored approaches. While a beginner may see improvements regardless of training order, an elite endurance athlete may need a highly specific sequence to maximise performance.

The Study: Investigating Training Sequence

To address these challenges, the study by Vikestad and Dalen (2024) sought to determine whether the sequence of endurance and strength training—ER or RE—affects endurance performance. Their systematic review analysed 15 randomised controlled trials involving 426 participants, providing a comprehensive look at this question.

The study focused on endurance performance metrics such as VO2max (maximal oxygen uptake), time to exhaustion (TTE), and maximal aerobic power (MAP). By comparing pre- and post-intervention changes in these parameters, the researchers aimed to identify whether one sequence consistently outperformed the other.

The trials included in the review varied in population, with participants ranging from untrained individuals to moderately active adults. Importantly, none of the studies involved elite or professional athletes. The interventions lasted a minimum of eight weeks, ensuring sufficient time for physiological adaptations.

The researchers assessed methodological quality using a modified PEDro scale and presented results as percentage changes in performance metrics. This approach ensured a robust analysis of the available data.

Results of the Study

The results revealed that both ER and RE sequences led to significant improvements in endurance performance. VO2max, a key indicator of aerobic fitness, increased across almost all studies, with minimal differences between the two sequences. In a few cases, ER demonstrated slight advantages, particularly for high-intensity endurance training.

Time to exhaustion (TTE) also improved significantly in both groups. However, ER showed marginally better results in studies where endurance sessions were performed at high intensity. This suggests that starting with endurance training may be advantageous when the primary goal is to enhance high-intensity aerobic performance.

Maximal aerobic power (MAP) and lactate threshold, other critical measures of endurance capacity, exhibited similar improvements in both ER and RE sequences. This underscores the idea that for many endurance outcomes, the sequence of training may not be a decisive factor.

Interestingly, the review noted that strength adaptations sometimes favoured the RE sequence. This may be due to the reduced interference effect when strength training is performed first, allowing for more effective neuromuscular and hypertrophy gains.

Overall, the study concluded that while ER may offer small advantages for high-intensity endurance adaptations, the sequence of training has minimal impact on general endurance performance. These findings are especially relevant for recreational or moderately trained individuals.

Implications for S&C Coaches

The findings of this study have several important implications for S&C coaches. First, they suggest that the sequence of training should be guided by the athlete’s primary goals. For endurance athletes focusing on high-intensity performance, prioritising endurance training may yield marginally better results. Conversely, clients aiming to maximise strength should consider starting their sessions with resistance training.

The minimal differences observed between sequences highlight the importance of flexibility in programme design. Coaches can adapt training schedules based on logistical constraints, such as time availability and access to facilities, without worrying about significantly compromising results.

The study also reinforces the value of recovery in concurrent training. Scheduling sessions with at least six hours between them can minimise interference effects and optimise performance in both training modes. For clients with packed schedules, creative solutions like alternating muscle groups (e.g., upper-body strength and cycling endurance) can help maintain training quality.