Journal of Strength and Conditioning Research: June 2022 - Volume 36 - Issue 6 - p 1506-1510 doi: 10.1519/JSC.0000000000003412

PURPOSE:

Strength and muscle mass improvements are dependent on exercise intensity. Therefore, this study attempted to verify whether 53 healthy young adults underestimated exercise intensity in the bench press (BP), biceps curl (BC), and l45° leg press (LP). The subjects were asked to estimate the amount of resistance they use to complete 10 repetitions (10-RM) in those exercises during their  workout routines.

PROCEDURES:

Following a brief warm up the subjects completed as many repetitions as possible with that estimated 10-RM resistance until they reached the concentric failure:

   § Deviations from data normality were found by using Levene's test.

   § The number of repetitions per exercise within sex was tested by using Friedman's test.

   § The Conover's post hoc and Kruskal–Wallis tests were used to compare the number of repetitions between sex and resistance training experience.

IMPORTANT: Encouragement and motivation was provided by practitioners to assure a maximum number of repetitions were performed with the estimated 10-RM resistance.

CONCLUSIONS:

The Spearman test was used to correlate the number of repetitions and training experience.

The Conover's post hoc and Kruskal–Wallis tests were used to compare the number of repetitions between sex and resistance training experience.

The number of repetitions completed for both groups (male and female) was  greater than 8–12 repetitions for BC, LP, and BP of the female group, except for men who only performed around 8–12 repetitions on BP.

Frequency of maximal repetitions reached for 8–12 repetitions for women was 12% for BP, 28% for BC, and 28% for LP.

The frequency men reached was 46.5% for BP, 14.3% for BC, and 14.3% for LP.

Women underestimate exercise load more than men.

IN PLAIN ENGLISH:

When left to their own discretion, many well-intended resistance training participants normally use resistances that are too light for the prescribed number of repetitions. That can decrease the effect of all sets performed and ultimately lead to less than maximum results.

It also reveals the importance of having a competent trainer or training partner that can encourage more effort/more repetitions to further enhance the quality of sets due to the aforementioned fact. Many “leave something behind” due to either being “soft,” clueless as to what hard work truly is, or being misled by popular print or Internet programs that prescribe arbitrary plans such as “3 x 10” or “5 x 8.”