Concurrent strength and endurance training: the best of both worlds?

Whether you’re a cyclist, runner, swimmer or triathlete, most of what determines your performance is determined by aerobic fitness and endurance capacity. However, when’s all said and done, an endurance athlete who has good strength as well as good endurance will always perform better than one who has good endurance but poor strength. It’s not just that strength training can reduce the risk of injury; numerous studies have shown that by incorporating heavy strength training into an endurance programme, endurance performance itself can be enhanced^(1-5).

The challenge of strength training

Despite our growing understanding of the value of strength training for endurance athletes, many athletes struggle to incorporate strength sessions into their endurance training programmes. There are a number of reasons for this including:

• The types of training needed to build strength and endurance are quite different, which means different types of training sessions (for example adding in gym work), and that in turn means more commitment in terms of time and organisation.
• The practicalities and knowhow of adding in strength sessions to an endurance programme, without harming the quality of the endurance sessions.
• The (incorrect) belief that strength training could result in ‘bulky’ muscles, leading to weight gain and worse endurance performance.

There’s also another complication; some studies have suggested that that endurance training performed within 24 hours of strength training can significantly reduce the benefits of that strength training, which further complicates the practicalities of timetabling sessions for maximum overall gains. Hardly surprising then that many endurance athletes concentrate on endurance training with minimal emphasis on strength! However, new research by Swedish scientists suggests that by training strength and endurance simultaneously (concurrent training), we might be able to have our cake and eat it⁽⁶⁾.

The research

A number of previous studies have examined the effects of adding strength training to an endurance programme. However, this study provides a different perspective looked at the effects of adding two different types of endurance training to a strength programme. In particular, the researchers wanted to find out the effects of six weeks of concurrent training incorporating either low-volume, high-intensity interval training, or high-volume, medium-intensity continuous endurance training, on the strength and power of highly-trained individuals.

All of the 16 subjects performed the same strength sessions, which consisted of 10 minutes of cycling at 100 watts (to warm up), followed by four sets of parallel squats with a light to medium loading (40–80% of 1RM). Thereafter, the participants performed 5 sets of 2 reps of parallel squats at or greater than 90% of 1RM (Mondays and Fridays) or 2 sets of 5 reps at or greater than 80% 1RM (Wednesdays). All sets were performed to failure or close to failure.

Fifteen minutes after completing each strength-training session, the athletes completed one of two types of endurance training session. These were added were:

• High intensity cycling interval group – 8-24 sets of 20-second intervals at 150% of sustainable maximum aerobic power (ie very intense!).
• High-volume, medium intensity cycling group – 40-80 minutes of steady state riding at 70% of VO2max (moderate intensity.

The findings

The key findings were as follows:

• The athletes’ parallel squat performances improved in both the continuous endurance training group and in the high-intensity interval training group (by 12% and 14% respectively). Moreover, there were no differences between the two groups.
• Measure of aerobic (endurance) capacity showed that there were no gains in aerobic fitness in the continuous group. However, the high-intensity group improved their maximum oxygen uptake (VO2max) values by an average of 3%.

Sports Performance Bulletin verdict

There were a number of positives to emerge from this research. Firstly, both the groups made strength gains, suggesting that adding in some endurance training immediately following strength training did NOT render the strength training ineffective. In other words, if time is tight, performing a combined (concurrent) strength and endurance workout can be a worthwhile strategy.

Secondly, it’s worth noting that the high-intensity interval group made significant aerobic gains compared to the continuous group, despite performing a much lower volume of total training. This suggests that when time is tight, high-intensity intervals are a more effective method to develop aerobic fitness. It also worth noting that the resistance training did NOT have a detrimental effect on endurance capacity in the continuous group either, which (as we mention before) is something that some endurance athletes worry about. The researchers themselves concluded by saying: “Since VO2max improved only after resistance training combined high-intensity training, and this is a time efficient protocol, we recommend this type of concurrent endurance training.”

Practical suggestions

Strength training can improve your performance (by making your muscle efficiency higher and reducing your injury risk). The best way for endurance athletes to achieve this is to add some specific strength training into their endurance programme.

• Strength sessions should be short and low-volume, high-intensity in nature (6-8 reps per exercise).
• For cyclists and runners, lower-body exercise such as squats, lunges and leg presses are recommended. For swimmers, some upper-body exercises such as front-grip pull ups are recommended.
• Adding in some plyometric training can further boost muscle efficiency (particularly for runners) by helping to increase limb stiffness.
• If you train on separate days, try to ensure your high-intensity endurance and strength sessions are performed as far apart as possible to allow maximal recovery in between sessions. If you want to try concurrent training sessions, you can combine strength and endurance; perform your strength training first, then move onto endurance training. This endurance training appears to be more effective when performed as high-intensity intervals.
• Begin with just one strength training session per week. This can be increased to two per week in the off season, when your endurance training volume is reduced.

References

1. Scand J Med Sci Sports. 2002 Oct;12(5):288-95
2. J Strength Cond Res. 2005 Nov;19(4):826-30
3. J Strength Cond Res. 2010 Aug;24(8):2157-65
4. Med Sci Sports Exerc. 2008 Jun;40(6):1087-92
5. J Strength Cond Res. 2006 Nov;20(4):947-54
6. J Sports Sci Med. 2018 Jun; 17(2): 167–173

 See also the following articles: