In an attempt to find a relationship between emotions and an athlete's best and worst performances, Cooper et al. recruited 13 elite male and female athletes from varying sports. They then had them recall their subjective best and worst strength and conditioning training sessions.

Results

What the researchers found was that during the best workouts, athletes experienced significantly greater feelings of confidence, motivation, and energy. They also had significantly less feelings of being fatigued, tired, discouraged, and lazy compared to those who recalled their worst workout ever.

I don't think the relationship between memories of a best-ever performance and feelings of confidence, motivation, etc. is a surprise to anyone. But what if over the long term, increases in confidence and motivation correlated with greater strength gains beyond what can be achieved with just training alone?

It appears plausible according to this next study that used motivating self-talk and mental imagery.

Researchers used 44 males in combat sports as participants. They were split into three groups: a mental imagery group, a mental imagery plus motivating self-talk (MIS) group, and a control group with neither imagery nor self-talk.

All groups trained three days a week, but following the workouts the mental imagery group and MIS group sat and imagined themselves doing the workout they just did. They would focus on the movements and imagine themselves performing it as perfectly as possible.

The MIS group also wrote down any negative self-talk that occurred during the training session and then were asked to come up with positive sentences to repeat to themselves in place of the negative ones, either out loud or in their head while performing the exercises.

What kind of training did they do? Their physical training intervention was focused on increasing the bench press, a medicine ball throw, a countermovement jump, and a half squat.

Results

Countermovement jump, half squat, bench press, and medicine ball throw were significantly greater in the MIS group than the control group following the intervention.

In the bench press and half squat, the MIS increased on average 13.5 kg (nearly 30 pounds) and 24.4 kg (about 54 pounds) respectively.

Meanwhile the control group increased on average 6.7 kg (about 15 pounds) and 8.1 kg (around 18 pounds) for the bench press and half squat respectively. After 10 weeks there was basically a DOUBLING of strength gains in the MIS group compared to the controls.

Self-efficacy and motivation were significantly greater post intervention in the MIS and MI (mental imagery and the mental imagery plus positive self-talk) groups compared to the control group.

Across all measurements, average percent change from pre to post measurements increased from the control group to the mental imagery group and then the imagery plus self-talk group. So the more positive interventions, the better their performance.

You might've already had a hunch that your emotions could affect your physical performance. And now science proves it.

So if you want to take advantage of this phenomenon, consider the use of long term motivational self-talk and mental imagery, which can boost feelings of confidence and motivation. In the second study, these mental tactics were associated with increased strength gains.

1. Cooper JJ et al. Optimal emotional profiles for peak performance in strength and conditioning. J Strength Cond Res. 2021 Mar 1;35(3):833-840. PubMed.
2. Slimani M et al. Effects of cognitive training strategies on muscular force and psychological skills in healthy striking combat sports practitioners. Sport Sci Health. 2016;12:141–149.