3 second workout just 3 times a week: Does it work, what muscles to engage and how

When you move the weight away from your shoulder in a bicep curl, this movement comprises an eccentric contraction. (Photo by Andres Ayrton via Pexels)

Fitness enthusiasts are constantly seeking effective and efficient ways to optimize their workouts. A recent study published in the European Journal of Applied Physiology posits that doing one eccentric bicep contraction for 3 seconds a day for a minimum of 3 days a week significantly improved muscle strength.

Understanding Eccentric Contraction

For those unfamiliar with the term eccentric contraction, let’s first understand that. It refers to the muscle action wherein the muscle elongates and lengthens under tension while producing force, such as in the biceps curl exercise when we lower the arm from the top towards the waist in a slow and controlled manner while holding a heavy weight. As opposed to that, concentric contraction refers to the muscle action wherein the muscle shortens under tension while producing force, such as in the biceps curl exercise when we bring our arm towards the shoulders as fast as possible with good form and a neutral spine while holding heavy weight. Thirdly, an isometric contraction is one in which the muscles are tensed up without any motion, with no change to muscle length.

Evaluating the Study’s Claim: The PICO Framework

At face value, the study’s claim sounds promising and remarkably convenient; a mere 3 seconds to build significant strength. But how true is this because one would expect a rigorous methodology to back such a profound claim? We used the gold standard of scientific analysis, the PICO framework, to critically decipher this study’s assertion to separate facts from fiction.

What Does PICO Mean?

• P (Population): The target audience or group participating in the study.

• I (Intervention): The activity or treatment being investigated.

• C (Comparison): What the intervention is being compared to.

• O (Outcome): The results or effects of the intervention.

Population: Missing Background Information

The study involved 26 healthy young adults, but crucial information about their backgrounds, such as fitness levels and training experience, is missing. Without these details and with a small and uniform demographic of participants, the universality of the study’s claims becomes questionable, as the efficacy of intervention varies across different demographic and fitness groups due to individual differences.

Intervention: Practicality and Methodological Flaws

The participants were divided equally into two groups, performing a single 3-second eccentric contraction for either two days a week (2DW) or three days a week (3DW) over four weeks. However, the lack of randomization in group assignments introduces a risk of selection bias, potentially influencing the desired outcome. Experiments that randomly assign participants to a study group and control group are known as randomized controlled trials (RCTs). RCTs are not only one of the ways of conducting experiments but rather the only way to conduct experiments to establish reliable knowledge.

Furthermore, using an isometric dynamometer that was used in the study to measure the participant’s strength levels and an isokinetic dynamometer that was used to conduct eccentric contractions is impractical for regular engagement, as it requires specialized equipment, or we have to take assistance from a trainer or partner to give us the heavyweight at the top of the bicep curl so that we can do maximal eccentric contraction over 3 seconds if we don’t have access to these dynamometers. Additionally, the maximal eccentric contraction used in the study may pose a risk of injury, especially for inexperienced or elderly individuals.

The duration of only 3 seconds a day raises concerns, as most strength training research emphasizes sets and repetitions rather than mere seconds. Established strength training recommendations by reputable organizations such as the American College of Sports Medicine advocate performing various exercises for each major muscle group at least twice a week on non-consecutive days with one set of 8 to 12 repetitions for healthy adults or 10-15 repetitions for older and frail individuals to promote muscle strength and endurance. Thus, the proposed 3-second framework lacks empirical support.

Comparison: The Missing Control Group

The study lacks a control group that could have performed regular concentric contractions or no exercise for comparison. Without a control group, evaluating the actual effectiveness of eccentric contractions becomes challenging. Unanswered questions include whether eccentric contractions outperform concentric contractions or the comparative benefits of eccentric training for those not exercising.

Outcome: Limited Scope and Modest Results

The proposed intervention overlooks essential elements of an effective strength training program, such as progressive overload, individualization, and periodicity. These principles ensure continuous muscle adaptation and prevent plateaus or overtraining, limiting the study’s approach.

Furthermore, the modest improvement of 2.5 percent and 3.9 percent in concentric and eccentric strength after four weeks cannot be considered significant, and over time, these gains may diminish due to muscular adaptation. Additionally, there was no discernible increase in isometric strength or muscle thickness, which is vital for combating conditions like sarcopenia, especially as we age and seek to maintain physical independence and enhance our quality of life.

Whereas if we look at the literature on the benefits of traditional strength training protocol involving at least three sets with 10-15 repetitions of exercise done over four weeks, we see around 15 percent, 20 percent and 25 percent gain in isometric, concentric and eccentric strength, respectively. The icing on the cake is that there are gains in muscle thickness too of around 4 percent with conventional strength training protocol, where we go through both concentric and eccentric phases of exercises for multiple sets and reps.

The benefits of an exercise routine are dose-dependent. Too little an amount will not lead to significant gains as an adaption to the activity will be quick. Thus instead of looking for less exercise, we should be looking for an optimal one. After all, we only get returns to the tune of what we invest in terms of our time and energy.

Actionable Takeaway: A Balanced Approach

While the allure of a mere 3-second workout is tempting, we should approach this claim with caution. Until further research provides a more comprehensive understanding, consider integrating eccentric contractions into your regular workout routine as part of a broader, well-rounded approach:

Incorporate Eccentric Training: Focus on the eccentric (lengthening) phase within your regular bicep workouts by taking 3-5 seconds to lower the weight.

Always Prioritize Form: Regardless of the duration, ensure you perform exercises with proper form to reduce the risk of injury.

Aim for Longer Durations: Instead of relying solely on 3 seconds, use multiple sets and repetitions for tangible strength gains.

Stay Inquisitive: Approach all fitness claims with an open and critical mind. Rely on evidence-based practices when in doubt.

Consult with Fitness Professionals: If you are new to eccentric training, seeking guidance can ensure you execute movements safely and effectively.

Conclusion: A Balanced Perspective

The study underscores the importance of eccentric training, often overshadowed by concentric exercises. Yet, it might oversimplify the multifaceted nature of strength training. Suggesting gains from merely three seconds of a daily routine may lead to unrealistic expectations and subsequent demotivation. Although the claim that “three-second eccentric bicep contractions over three days significantly improve muscle strength” is captivating, it warrants deeper scrutiny.

While eccentric exercises can induce pronounced muscle adaptations, the time factor remains vital. High-intensity routines, like plyometrics, often extend beyond 3 seconds and complement other workout types. The fitness community should meld eccentric training principles with existing practices rather than supplanting them. Abiding by the American College of Sports Medicine’s guidelines—comprising at least two comprehensive strength-training sessions weekly—is pivotal for muscle growth and stamina.

In summation, eccentric training is undoubtedly beneficial, but the study’s methodology appears lacking—approach such assertions with discernment and stick to evidence-backed training guidelines. Fitness, after all, isn’t a mere 3-second endeavour but a balanced, consistent journey.