In this article, we continue from where we left off in the previous one, focusing on the importance of strength training for endurance athletes.

In this article, we pick up where we left off in the previous one. How does strength training affect muscle performance, and why should every endurance athlete consider developing strength?

Also Read: Strength training for endurance athletes – part 1

Heavier Weights for Greater Benefits

According to Maastohiihto.com, training with heavy weights (85 – 95% of maximum) can improve both short-term and long-term endurance. This improvement is due to changes in the neuromuscular system rather than an increase in aerobic capacity. Fast-twitch type IIa muscle fibers grow, while type IIx fibers (even faster-twitch fibers) decrease as a result of maximal strength training.

Maximal muscle strength and muscle force production speed also increase. When maximum strength increases while body weight remains roughly the same, the athlete has more relative strength to use. This means that a single ski push or running step no longer consumes as large a portion of the athlete’s total strength, leading to improved performance.

As a result of these neurological changes, maximal strength training delays the onset of fatigue in sub-half-hour performances. This has been observed in elite runners, cyclists, and skiers. For example, after an 8-week combined strength and endurance training period, runners improved their maximal test running time by approximately 21% without changes in maximal oxygen uptake. The benefits of strength training have also been demonstrated in longer performances.

Contrary to common belief, recent studies have not shown that maximal strength training reduces muscle capillarization. In some studies, strength training has even been found to stimulate the formation of muscle capillaries and increase capillary density. Increased capillarization enhances oxygen transport to muscles and the removal of waste products during exercise, thus improving endurance performance. Combined endurance and maximal strength training can increase strength without compromising endurance qualities.

More Efficient Force Production

Maximal strength training, as well as speed-strength training, leads to faster force production and prolongs muscle relaxation. Faster force production in cycling means that there is more time for recovery during each pedal stroke, which improves performance. In skiing, rapid force production enables longer recovery periods, contributing to endurance in longer performances. In running, the stride becomes more economical and efficient due to improved force production.

When muscles contract more quickly and efficiently, the blood flow to the muscles increases. This results in improved fuel delivery to the cells and waste removal, enhancing endurance performance. In endurance sports, aerobic energy production cannot occur without sufficient oxygen and nutrients. Similarly, sustaining high-intensity efforts becomes more challenging as lactic acid accumulates in the muscles without adequate removal.

In many sports, such as road cycling, cross-country skiing, and middle to long-distance running, the ability to accelerate towards the end of a race can be a crucial factor for final rankings. Strength training enhances the capacity for rapid force production, improving chances in end-of-race sprints. Furthermore, fatigue towards the end of a performance can make maintaining proper form difficult, especially in running. Maximal strength training allows athletes to sustain their running posture for longer, keeping their performance economical and reducing energy expenditure, which can help prevent overuse injuries.

Strength Training Enhances Efficiency

Efficiency is a significant factor in endurance performance. The less energy an athlete consumes at a specific speed or power output, the longer they are likely to sustain their performance. In addition to oxygen consumption, an efficient athlete tends to have a lower heart rate and lower lactate levels at a given intensity than a less efficient athlete.

The effects of maximal strength training on efficiency are substantial. Elite endurance athletes have been found to improve their efficiency through combined strength and endurance training compared to endurance training alone.

For example, Paula Radcliffe reached the top level in endurance running through strength training. By incorporating heavy weights alongside her running training, Radcliffe’s efficiency, meaning her oxygen consumption at a given pace, improved significantly within a few years. Despite a slight decrease in oxygen consumption during the same period, she set world records in women’s marathon running twice in the early 2000s.

What, When, and How Much?

The benefits of maximal strength training become apparent when the training period is long enough and performed at a high enough intensity. Less than an eight-week training period has shown little benefit, and strength training at less than 80% of maximum intensity has not significantly improved endurance performance.

To derive the maximum benefit from a strength training period, researchers recommend designing a program lasting at least eight (and up to 20) weeks, incorporating maximal strength training with heavy weights (85 – 95% of maximum) alongside endurance training. Good exercises for this purpose include squats and deadlifts. For example, start with 4 sets of 4 repetitions at 85-95% of your one-rep max (1RM) with 3 minutes of rest between sets. The advantage of maximal strength over plyometrics is the absence of impact, which reduces the risk of injury.

Explosive strength training (speed strength training) is also beneficial and produces similar responses to maximal strength training. Explosive strength is trained using various types of jumps with either light weights or body weight resistance. Proper technique is crucial when performing jumps. It is advisable to start cautiously and avoid excessive jumping in the initial sessions, as sudden changes in training can increase the risk of injury.

As an example, consider drop jumps performed from heights of 20cm, 40cm, and 60cm. Land with nearly straight legs and aim to rebound immediately upwards like a spring. Your calf muscles should do the work, not your quadriceps, so it’s important not to bend your knees excessively during ground contact. Try 2 sets of 10 repetitions at each height with 15-second rests between repetitions and 2-minute rests between sets.

Circuit training can also be effective and targets slightly different attributes than maximal strength but can be incorporated into an endurance athlete’s program throughout the year. During the competition season, light circuit training has the advantage of not causing muscle stiffness, as heavy strength training might. The only form of training that endurance athletes should aim to avoid is hypertrophic training (6 – 12RM), which increases muscle size and body weight.

In Conclusion

Before engaging in strength training, a thorough warm-up is essential to minimize the risk of injury. A light jog or bike ride for about 15 minutes, more or less depending on the individual, can serve as a warm-up. However, it’s important not to jog for too long, as excessive fatigue during the warm-up can diminish the benefits of the main workout, the strength training. After the workout, any cool-down method can be used. Swimming or water jogging effectively aids muscle recovery, so if a swimming pool is nearby, it’s worth taking advantage of it.

When planning strength training, it’s crucial to consider the athlete’s current strength levels, age, and training or competition phase. The training should be individualized to align with each athlete’s specific goals and starting point. By doing so, a successful strength period can be executed, resulting in significant positive effects on an athlete’s performance.

References:

• Aagaard, P. & Andersen, JL. Effects of strength training on endurance capacity in top-level endurance athletes. Scand J Med Sci Sport 2010; 20 (2): 39-47.
• Ramirez-Campillo ym. 2014. Journal of Strength and Conditioning Research. In press.
• Mikkola, J., Vesterinen, V., Taipale, R., Capostagno, B., Häkkinen, K. & Nummela, A. Effect of resistance training regimens on treadmill running and neuromuscular performance in recreational endurance runners. J Appl Sports Sci 2011; 29 (13): 1359-1371.

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