Microdosing of Flywheel Training: Effects of Low Versus High Training Frequency on Muscle Mass, Strength, and Power.
Sergio Maroto-Izquierdo, Marina Gómez, Susana López-Ortiz, Fernando Martin-Rivera, Masatoshi Nakamura, Oliver Gonzalo-Skok
International Journal of Sports Physiology and Performance May 4, 2026 DOI: 10.1123/ijspp.2025-0582 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 30 |
| Population | Active individuals |
| Intervention | Flywheel resistance training |
| Duration | 6-week intervention |
| Topics | Microdosing |
| Keywords | Eccentric overload Muscle architecture Neuromuscular adaptations Resistance training Ultrasounds |
| Key findings | Microdosing flywheel resistance training (5 sessions/week) significantly increased vastus lateralis and rectus femoris muscle thickness, fascicle length, and fascicle angle, whereas once-weekly training did not, and both groups similarly improved strength and jump performance. |
Abstract
This study compared the effects of low-frequency flywheel resistance training (FRT, 1 session/week) and microdosing FRT (5 sessions/week) on muscle architecture, strength, and vertical jump performance in active individuals. Thirty participants were randomized into a microdosing group (MDG, n = 15) or a control group (CG, n = 15). Both groups completed equalized weekly training volumes (30 sets over 6 wk) using a flywheel leg press. The MDG performed one set daily, whereas the CG performed 5 sets once weekly. Vastus lateralis and rectus femoris muscle thickness, vastus lateralis fascicle length and angle, maximal voluntary isometric contraction in the half-squat exercise, countermovement and drop jump performance, rating of perceived exertion, and delayed-onset muscle soreness were assessed preintervention and postintervention. MDG showed significant (P < .001) increases in muscle thickness (vastus lateralis: 9.8%, 0.21 cm, effect size [ES] = 0.41; and rectus femoris: 7.9%, 0.18 cm, ES = 0.34), fascicle length (11.8%, 0.96 cm, ES = 0.81), and fascicle angle (14.2%, 2.29°, ES = 1.16), drop jump RSI (24.4%, ES = 0.97), and drop jump take-off velocity (5.7%, ES = 0.27) while CG showed no significant changes. Both groups showed improved maximal voluntary isometric contraction (MDG: 27.4%, ES = 0.72; CG: 18.6%; ES = 0.48), countermovement height (MDG, 7.7%, ES = 0.34; CG: 5.9%, ES = 0.17), and countermovement mRSI (MDG, 32.1%, ES = 0.98; CG: 34.0%, ES = 0.60) with no intergroup differences. However, MDG reported significantly (P < .001) lower rating of perceived exertion and delayed-onset muscle soreness scores throughout the intervention. FRT microdosing improved muscle architecture, while strength and power gains were similar to low-frequency FRT. Importantly, microdosing reduced fatigue and soreness, offering a practical alternative during competitive congested schedules or in rehabilitation settings.
Comparable studies
Other randomized controlled trials on microdosing, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Use of microdosing to predict pharmacokinetics at the therapeutic dose: Experience with 5 drugs Volunteers | 2006 | Crossover study | |
| Self-blinding citizen science to explore psychedelic microdosing. Participants who microdose psychedelics | 2021 | Self-blinding citizen science initiative with placebo control | n = 191 |
| Microdosing with psilocybin mushrooms: a double-blind placebo-controlled study Individuals starting to microdose with psilocybin mushrooms (Psilocybe cubensis) | 2022 | Double-blind placebo-controlled experimental design | n = 34 |
| Preliminary Report on the Effects of a Low Dose of LSD on Resting-State Amygdala Functional Connectivity. Healthy young adults, 18 to 35 years old | 2019 | Randomized controlled trial | n = 20 |
| Acute Mood-Elevating Properties of Microdosed Lysergic Acid Diethylamide in Healthy Volunteers: A Home-Administered Randomized Controlled Trial. Healthy male volunteers | 2023 | Randomized controlled trial | n = 80 |
Citations in the library
Cites 2
- Microdosing: A Conceptual Framework for use as Programming Strategy for Resistance Training in Team Sports Strength & Conditioning Journal June 15, 2023
- Microdosing: Old Wine in a New Bottle? Current State of Affairs and Future Avenues. International Journal of Sports Physiology and Performance October 6, 2022