Strength for athletes: maximize the bang, limit your buck!

Here at SPB, we’ve explored the benefits of strength training for athletes in great depth over recent years – and for good reason. That’s because, a very large body of research has accumulated showing that strength training can improve performance in a wide range of athletes. It’s not just that the increased resilience of stronger muscles can help reduce the risk of injury – both those arising from inherent weaknesses and those of strength imbalances between different muscle groups^(1,2). And it’s not only about the gains in strength and power⁽³⁾, which can help athletes in sports where strength, power, speed, force and acceleration are important.

Less appreciated

What’s less appreciated is that strength training can also seriously benefit endurance athletes by increasing muscle efficiency, which means that muscles require less oxygen to sustain a sub-maximal pace, resulting in less fatigue^(4-8). This increase in muscle efficiency is more technically known as ‘muscle economy’ – important since research shows that high levels of muscle economy are strongly linked to endurance performance^(9,10). Indeed, research shows that for events of over 20 minutes’ duration just two factors – maximum aerobic capacity (VO2max) and running economy - can account for 92% of the variance in endurance performance⁽¹¹⁾.

Getting strength-training ‘bang for buck’

Given that adding strength training sessions to an athlete’s program will almost certainly produce performance gains, the question is how best to structure those sessions. Strength training requires mental and physical energy, but so do the athlete’s sport-specific training sessions. There’s only so much energy an athlete has before risking excessive fatigue, which means that any strength training needs to be as productive as possible so the benefits can be had while minimizing demands on the athlete’s physical reserves. In plain English, athletes need biggest bang per unit of time and effort invested!

There are many, many permutations of strength training programs, all of which can impact the energy and effort required and the benefits gained. Among the factors that can be manipulated are:

·        Choice of strength exercises.

·        Order of strength exercises.

·        Number of sets of each exercise.

·        Resistance or weight used in each exercise.

·        Number of reps in each exercise set.

·        Optimal rep speed.

·        The rest length between sets.

·        The frequency of strength sessions and how they are sequenced into an overall training program.

In previous SPB articles, we have looked at what the recent research says about how these factors can be manipulated for superior gains, including exercise order, how to combine strength training into a mixed session, how many reps/how hard to push in each set, optimal rep speed, rest length between sets, training frequency, and many others. Of these, how hard to push during each set is one of the most critical factors because it plays a major role in determining the size of the stimulus generated, but also the level of fatigue experienced.

How close to failure?

In order to create a strength/muscle growth stimulus in a training session, muscles need to experience a degree of overload in that session. This overload involves pushing the muscle fibers to do more than they are accustomed to. It follows that when performing a strength exercise to induce overload, it is necessary to approach or reach the point where the muscle fibers cannot do what is being demanded of them – the so-called ‘failure point’. But how close to failure should you be working to achieve maximum results?

While it has been traditional among strength athletes and bodybuilders to work right up to failure in order to promote maximum strength and muscle growth, more recent research suggests that actually, there are no additional gains working to failure compared to quitting a couple of reps before failure⁽¹²⁾. However, other studies have found that when the loading is light (below 50% of 1-rep max), working to failure does generate better strength and muscle growth gains⁽¹³⁾. Yet more research found that rather than working to failure or not, what really seems to make the difference is the total volume of high-quality, high-load reps accrued in a strength session⁽¹⁴⁾.

With the uncertainty in these findings, you might be thinking that in order to be on the safe side and ensure maximum gains from a strength session, you should just go ahead and work to failure anyway. However, working to failure comes at a price – a price that may work against the athlete:

·        Performing sets to momentary muscular failure can incur very high levels of neuromuscular fatigue that impairs the quality of the movement during the later reps, the ability to perform additional sets and therefore, a reduced overall training stimulus in a strength session⁽¹⁵⁾.

·        Some research suggests that the extra muscle damage caused by working to failure compromises protein synthesis directed towards muscle hypertrophy. In short, the extra protein synthesis that would have been directed to muscle growth after a strength workout is instead directed to repair of damaged muscle fibers⁽¹⁶⁾.

·        Athletes who do not regularly work to failure can experience a large amount of delayed-onset muscle soreness (DOMS), which may impair their ability to train for quite a number of days afterwards!

Uncertainties

Some research has reported that as you steadily accumulate more and more reps in a set, the strength gains from that set steadily increase, but once you get within 2-3 reps of failure, there are no more gains to be had⁽¹⁷⁾. But this is complicated by the fact that in many studies in strength training almost to failure (ie leaving two or three reps in reserve), estimations of the reps in reserve (ie when to terminate the set) have been very variable and uncertain - especially where the participants are less experienced strength trainers, and also down to the fact that individuality also seems to play a large part in determining just how much is left in the bank for the end of the set⁽¹⁸⁾.

Looking at the scientific data as a whole on this topic, we can conclude that while working to momentary muscular failure is undoubtedly effective for promoting muscle growth, reaching close proximities to failure may also be sufficient, even in experienced resistance-trained individuals. If the latter is the case, this is a win-win strategy as it would mean that maximum gains can be achieved without the drawbacks of working to failure.

The problem however is that it’s difficult to make firm recommendations for trained athletes on whether they should work to failure or keep some reps in reserve as only one study has ever been conducted on this topic where the participants were resistance trained⁽¹⁹⁾. While this found that training near to failure was as effective in promoting muscle growth as training to actual failure, it studied only a small number of participants who trained using just one exercise, and where there was no ‘reps in reserve’ strategy – ie the participants terminated the set randomly when they felt tired, rather than keeping to a reps in reserve goal (eg terminating the set once they knew they had only two possible reps left in the tank).