Is 60 seconds of training each month enough for stronger biceps?

In a study in which 894 Australian individuals (age: 25 - 54 years) were surveyed regarding motivations and reasons for not exercising, the most frequently cited reason was not having enough time [1]. For inactive people, the time factor seems to be the main argument against sports.

Since exercise and strength training are quasi medicine, it’s hardly surprising that research is striving to eliminate any barriers, such as time. The search for ways to optimise effectiveness and efficiency is ongoing.

Minimum training frequency of one maximum eccentric contraction

A few weeks ago, a Japanese research team investigated the question of efficiency and published an article on the topic of eccentric strength training [2]. The researchers wanted to know how often or how rarely you have to do an eccentric contraction lasting a maximum of 3 s (seconds) per week to significantly increase the strength in the biceps. For this purpose, they used results from a previously published study for which trainees performed a 3 s sustained eccentric contraction on 5 days per week over a study period of 4 weeks [3]. To determine the minimum weekly training frequency, the question the team now pursued was whether just 2 or 3 workouts, each with a 3 s maximal eccentric contraction, are sufficient to significantly increase strength. For this purpose, 26 young, healthy subjects (19 males and 7 females, age: 21 - 22 years) were recruited and randomly divided into two groups. Over a four-week period, 13 subjects each trained 2 times per week and 13 subjects each trained 3 times per week. The groups trained on Monday and Thursday or Tuesday and Friday (2 x week group); or Monday, Wednesday and Friday or Tuesday, Thursday and Saturday (3 x week group). As in the previous study with a training frequency of 5 days per week (Monday to Friday), the torque was examined.

A dynamometer was used for training. This is a device that can move a lever arm at a constant speed. This means that an angular velocity (°/s) can be specified and the subject pushes against it with the maximum force they can voluntarily generate. Among other things, this allows us to determine the force, at each joint position.

For the study, training was performed between joint angles of 100° and 10°, with 0° representing the fully extended arm. Thus, training was performed over a joint angle movement of 90°. To eccentrically load the biceps for 3 s, the researchers selected an angular velocity of 30°/s for the dynamometer setting and instructed the subjects to push against the downward-moving lever arm for 3 s with maximum voluntary force.

Results

The researchers investigated the following force magnitudes:

• Isometric force that can be generated over 3 s at the following joint positions: 20°, 55° and 90°
• Concentric force at an angular velocity of 30°/s and 180°/s
• Eccentric force at an angular velocity of 30°/s and 180°/s
• Average torque across all force variables

Ultrasound was also used to determine the muscle thickness of the trained arm to study the effects of training frequency on it.

The completed training volume (Nm s) is significantly different in all three groups (2, 3 and 5 times training per week) due to the study design. The highest volume was completed by the group that exercised 5 times (3658 ± 1051 Nm s ) per week. The group that exercised 3 times (2070 ± 508 Nm s) per week came next. The volume of the group with the smallest training frequency was 1233 ± 257 Nm s.

For all groups, the researchers now compared the torque averaged across all force variables in the first training session and compared it to the torque in the last training session in week 4. All groups were able to generate an equal amount of torque in the first training session. There was no difference between them. However, when comparing the first and last training sessions, it was found that the group that trained 5 times per week showed a significant increase of Δ15.7 ± 10.5%. This wasn’t the case for the other groups.
Using a magnitude detailed approach for each force showed that the group that trained 5 times per week was able to generate significantly more torque in the isometric measurements at all joint angles. In the group that trained 3 times per week, this was only the case with a joint angle of 20°. There was no statistically significant difference in the group that trained only 2 times per week.

Also, when looking at the concentric force that could be generated, there was a significant difference in the group that trained 5 times per week. The latter was able to generate higher torque at an angular velocity of 30°/s, but not at 180°/s. The other two groups showed no statistically significant difference.

For eccentric torque, both the group that trained 5 times and the group that trained 3 times showed a significant increase in torque compared to the baseline measurement at both angular velocities. No differences could be found in the group that trained only 2 times per week. Muscle size remained the same in all groups and didn’t increase significantly.

Conclusion and limitations

Producing maximum volitional force for 3 s and doing it at least 3 days a week helps you get stronger. But it won’t make your muscles grow. Due to the differences between the groups, the training frequency must be assigned a greater importance for this training method.

The study isn’t free from limitations. Whether the results can be generalised remains to be seen until other cohorts, such as older individuals and/or clinical cohorts, are studied. The question of how the increase in strength behaves over a longer study period can’t be answered with this study either. Future studies will show whether we see similar results in other muscle groups. In addition, the strength equipment, which is often still loaded with weight plates, makes it difficult to accommodate purely eccentric training. Maximal eccentric contractions can be dangerous for elderly patients or clinical populations too.

What the study does suggest, however, is that strength training can be done efficiently. The study largely invalidates the argument of not having time for something that, in terms of health, is very beneficial to our bodies. As a society, it’d be worth putting more value on the benefits of strength training to encourage a paradigm shift.

Take time for your muscles, or time will take your muscles.

References

1. Hoare E, Stavreski B, Jennings G, Kingwell B. Exploring Motivation and Barriers to Physical Activity among Active and Inactive Australian Adults. Sports. 2017;5: 47. doi:10.3390/sports5030047

2. Yoshida R, Kasahara K, Murakami Y, Sato S, Tanaka M, Nosaka K, et al. Weekly minimum frequency of one maximal eccentric contraction to increase muscle strength of the elbow flexors. Eur J Appl Physiol. Springer Berlin Heidelberg; 2023; doi:10.1007/s00421-023-05281-6

3. Sato S, Yoshida R, Murakoshi F, Sasaki Y, Yahata K, Nosaka K, et al. Effect of daily 3-s maximum voluntary isometric, concentric, or eccentric contraction on elbow flexor strength. Scand J Med Sci Sports. Scand J Med Sci Sports; 2022;32: 833–843. doi:10.1111/SMS.14138