Concurrent cycling and resistance training: Effects on hypertrophy and strength

<h2>Abstract</h2> <p>Concurrent cycling and resistance training represents a common practice among fitness enthusiasts who wish to develop both cardiovascular fitness and <a href="/terms/muscle-hypertrophy/" class="term-link" data-slug="muscle-hypertrophy" title="muscular hypertrophy">muscular hypertrophy</a> simultaneously. This review by Doma, Deakin, and Bentley (2019) examines the evidence for interference between cycling-based endurance exercise and resistance training adaptations, with particular attention to lower-body hypertrophy and maximal strength outcomes.</p> <p>The review synthesizes findings from 21 controlled studies and demonstrates that cycling, compared to running, produces significantly less interference with resistance training-induced hypertrophy. The predominantly concentric mechanical profile of the cycling pedal stroke minimizes eccentric-induced <a href="/terms/muscle-damage/" class="term-link" data-slug="muscle-damage" title="muscle damage">muscle damage</a> and residual neuromuscular fatigue in the quadriceps, hamstrings, and glutes. Steady-state cycling at Zone 2 intensities (65–75% HRmax) generates less interference than high-intensity cycling intervals, as the latter significantly depletes muscle glycogen and activates competing molecular signaling cascades. Critically, lower-body hypertrophy from resistance training is not significantly attenuated by cycling when sessions are separated by at least 6 hours, or when cycling is scheduled after resistance training on the same day. The review provides evidence-based guidance for individuals seeking to optimize both adaptations simultaneously.</p> <p><em>Keywords: cycling, <a href="/terms/concurrent-training/" class="term-link" data-slug="concurrent-training" title="concurrent training">concurrent training</a>, hypertrophy interference, concentric muscle action, resistance training, aerobic capacity</em></p>

<h2>Introduction</h2> <p>The <a href="/terms/concurrent-training/" class="term-link" data-slug="concurrent-training" title="concurrent training">concurrent training</a> interference effect presents a fundamental challenge for individuals who aspire to both muscular development and cardiovascular fitness. Since Hickson's seminal 1980 observation, research has consistently demonstrated that the molecular signaling pathways governing aerobic adaptation (primarily AMPK-mediated) and those governing <a href="/terms/muscle-hypertrophy/" class="term-link" data-slug="muscle-hypertrophy" title="muscle hypertrophy">muscle hypertrophy</a> (primarily <a href="/terms/mtor/" class="term-link" data-slug="mtor" title="mTOR">mTOR</a>-mediated) exhibit mutual inhibitory cross-talk under certain training conditions [1]. The practical question for the fitness practitioner is not whether interference exists, but rather which aerobic modalities and programming strategies minimize it.</p> <p>Cycling occupies a unique position in the concurrent training landscape. As the most commonly used indoor aerobic modality alongside resistance training, cycling is performed by millions of individuals daily on stationary bikes, spin bikes, and outdoor bicycles. Yet the specific interference characteristics of cycling have received less systematic attention than running, despite cycling's distinct biomechanical and physiological profile [2].</p> <p>The cycling pedal stroke involves knee flexion and extension, hip flexion and extension, and ankle plantar/dorsiflexion across a smooth circular path. Unlike running, which requires explosive ground-contact forces and substantial eccentric braking during the landing phase, the cycling motion is predominantly concentric in both the quadriceps (downstroke extension) and hamstrings (upstroke flexion). This concentric dominance theoretically limits <a href="/terms/muscle-fiber/" class="term-link" data-slug="muscle-fiber" title="muscle fiber">muscle fiber</a> microtrauma, inflammatory responses, and the mechanical disruption of <a href="/terms/sarcomere/" class="term-link" data-slug="sarcomere" title="sarcomere">sarcomere</a> organization that contributes to <a href="/terms/muscle-damage/" class="term-link" data-slug="muscle-damage" title="exercise-induced muscle damage">exercise-induced muscle damage</a> [3].</p> <p>Understanding these differences has practical implications for lower-body resistance training athletes (powerlifters, bodybuilders, track cyclists, team sport athletes) who wish to use cycling as a cardiovascular conditioning tool without compromising lower-body hypertrophy or maximal strength. This review evaluates whether cycling fulfills this promise, examining both acute interference (next-session performance effects) and chronic interference (long-term hypertrophy and strength outcomes) [4].</p>

<h2>Evidence Review</h2> <h3>Mechanical Profile of Cycling vs. Running</h3> <p>The quantitative difference in eccentric loading between cycling and running is substantial. During running at moderate speeds (10–12 km/h), peak knee extensor eccentric forces can exceed 3–4 times body weight during the deceleration phase of ground contact. During cycling, peak knee extensor forces are approximately 0.8–1.2 times body weight, predominantly concentric, with minimal eccentric loading [5].</p> <p>This mechanical difference translates directly to <a href="/terms/muscle-damage/" class="term-link" data-slug="muscle-damage" title="muscle damage">muscle damage</a> markers. Serum <a href="/terms/creatine-monohydrate/" class="term-link" data-slug="creatine-monohydrate" title="creatine">creatine</a> kinase (CK), a leakage enzyme released from damaged muscle fibers, rises to 800–1500 U/L after sustained running but typically remains below 300 U/L after equivalent-duration cycling at comparable intensities. Maximal voluntary contraction force loss, a functional marker of acute muscle damage, is typically 15–25% post-running versus 5–10% post-cycling [6].</p> <h3>Acute Interference: Resistance Training Performance After Cycling</h3> <p>Studies measuring resistance training performance following cycling sessions demonstrate that cycling-induced fatigue does affect subsequent training quality, but to a lesser extent than running:</p> <table> <thead> <tr> <th>Outcome Measure</th> <th>Post-Cycling Effect</th> <th>Post-Running Effect</th> </tr> </thead> <tbody> <tr> <td>Peak torque (isokinetic)</td> <td>-5 to -10% at 24h</td> <td>-15 to -20% at 24h</td> </tr> <tr> <td>Maximal voluntary contraction</td> <td>-5 to -8% at 24h</td> <td>-12 to -18% at 24h</td> </tr> <tr> <td>Total <a href="/terms/training-volume/" class="term-link" data-slug="training-volume" title="training volume">training volume</a> (sets × reps)</td> <td>-3 to -8%</td> <td>-10 to -18%</td> </tr> <tr> <td>Perceived readiness to train</td> <td>Moderately reduced</td> <td>Substantially reduced</td> </tr> </tbody> </table> <p>Recovery from cycling fatigue occurs within 12–24 hours in most trained individuals, compared to 24–48 hours post-running [7].</p> <h3>Chronic Interference: <a href="/terms/muscle-hypertrophy/" class="term-link" data-slug="muscle-hypertrophy" title="Hypertrophy">Hypertrophy</a> and Strength Outcomes</h3> <p>The most relevant evidence concerns long-term adaptations when cycling and resistance training are combined over weeks and months. A 2017 <a href="/terms/meta-analysis/" class="term-link" data-slug="meta-analysis" title="meta-analysis">meta-analysis</a> (n = 843) examined lower-body hypertrophy outcomes from concurrent cycling-resistance training versus resistance training alone. Key findings showed [8]:</p> <ul> <li>No statistically significant difference in quadriceps hypertrophy when sessions were separated by 6+ hours</li> <li>A small but statistically significant attenuation (–0.15 <a href="/terms/effect-size/" class="term-link" data-slug="effect-size" title="effect size">effect size</a>) in quadriceps hypertrophy when sessions were performed within 4 hours</li> <li>No significant difference in maximal lower-body strength (<a href="/terms/one-repetition-maximum/" class="term-link" data-slug="one-repetition-maximum" title="1RM">1RM</a> squat, 1RM leg press) across all separation conditions</li> <li>Zone 2 steady-state cycling produced less hypertrophy attenuation than <a href="/terms/hiit/" class="term-link" data-slug="hiit" title="HIIT">HIIT</a> cycling</li> </ul> <h3>Intensity Matters: Steady-State vs. High-Intensity Cycling</h3> <p>The intensity of cycling is a critical moderating variable. High-intensity cycling intervals substantially deplete muscle glycogen (up to 60% reduction in quadriceps glycogen after 45-minute HIIT cycling), creating greater AMPK activation that competes with <a href="/terms/mtor/" class="term-link" data-slug="mtor" title="mTOR">mTOR</a> signaling. Steady-state Zone 2 cycling (65–75% HRmax, moderate but sustainable effort) depletes substantially less glycogen and produces lower AMPK activation, resulting in smaller interference signals [9].</p> <p>This intensity-specific interference pattern suggests that athletes prioritizing hypertrophy should use Zone 2 steady-state cycling for concurrent conditioning, reserving HIIT cycling for phases where hypertrophy is less prioritized or when session separation (6+ hours) is guaranteed.</p>

<h2>Discussion</h2> <h3>Cycling as the Preferred Lower-Body Concurrent Modality</h3> <p>The collective evidence positions cycling as the superior aerobic modality for individuals performing lower-body resistance training, particularly when compared to running. The combination of lower eccentric muscle loading, faster recovery kinetics, and equivalent cardiovascular stimulus makes cycling a more "resistance-training friendly" form of cardio. This advantage is most relevant for bodybuilders, powerlifters, and team sport athletes who train lower-body resistance exercises 3–5 times per week and need a cardiovascular option that does not chronically compromise their primary training [10].</p> <p>However, the practical advantage of cycling over rowing is small. Both modalities share predominantly concentric mechanics and comparable interference profiles. The choice between cycling and rowing should therefore be based on personal preference, equipment access, injury status, and whether upper-body muscular involvement is desired as a training stimulus or avoided as interference with upper-body resistance training [11].</p> <h3>The Quadriceps Overlap Problem</h3> <p>An underappreciated complication of concurrent cycling and lower-body resistance training is the substantial overlap in the primary muscles stressed. Heavy squats, leg presses, and Romanian deadlifts all heavily load the quadriceps, hamstrings, and glutes. Cycling, even at moderate intensities, is a high-volume quadriceps exercise due to the repetitive knee extension pattern across hundreds of pedal strokes per session. The cumulative mechanical stress on the quadriceps from combined cycling and heavy leg training may exceed recovery capacity even when molecular interference effects are minimized [12].</p> <p>Practical management of this overlap involves adjusting cycling duration and intensity based on leg <a href="/terms/training-volume/" class="term-link" data-slug="training-volume" title="training volume">training volume</a> in the same week. On weeks with 3–4 heavy lower-body resistance sessions, cycling sessions should be shorter (20–30 minutes) and lower intensity. On weeks with reduced lifting volume, cycling volume can increase to maintain cardiovascular conditioning.</p> <h3>Upper-Body and Core Benefits of Cycling</h3> <p>Though cycling primarily conditions the lower body, significant engagement of the core (transverse abdominis, obliques), hip flexors (iliopsoas, rectus femoris), and, in standing positions (sprints), upper-body musculature provides broader conditioning value. Indoor cycling classes with upper-body resistance bands or outdoor road cycling requiring sustained upper-body postural control engage posterior chain and arm musculature more than commonly assumed [13].</p> <h3>Cycling Metrics for Training Prescription</h3> <p>Modern cycling technology (power meters, smart trainers) enables highly precise training prescription using power output in watts rather than heart rate. Functional threshold power (FTP), defined as the maximum power sustainable for approximately 60 minutes, serves as the reference point for cycling zone prescription. This metric is more reproducible and session-specific than heart rate, which can be confounded by factors like heat, <a href="/terms/caffeine/" class="term-link" data-slug="caffeine" title="caffeine">caffeine</a>, and fatigue [14].</p>

<h2>Practical Recommendations</h2> <h3>Cycling Intensity Zones (Heart Rate Based)</h3> <table> <thead> <tr> <th>Zone</th> <th>% HRmax</th> <th>Effort</th> <th>Duration Range</th> </tr> </thead> <tbody> <tr> <td>Zone 1 (recovery)</td> <td>55–65%</td> <td>Very easy, fully conversational</td> <td>Unlimited</td> </tr> <tr> <td>Zone 2 (aerobic base)</td> <td>65–75%</td> <td>Easy breathing, light effort</td> <td>30–90 min</td> </tr> <tr> <td>Zone 3 (tempo)</td> <td>75–85%</td> <td>Moderately hard, limited conversation</td> <td>20–45 min</td> </tr> <tr> <td>Zone 4 (threshold)</td> <td>85–92%</td> <td>Hard, unsustainable for long</td> <td>10–20 min</td> </tr> <tr> <td>Zone 5 (VO2max)</td> <td>92%</td> <td>Very hard, sprint intervals only</td> <td>2–8 min</td> </tr> </tbody> </table> <p>For <a href="/terms/muscle-hypertrophy/" class="term-link" data-slug="muscle-hypertrophy" title="hypertrophy">hypertrophy</a>-focused <a href="/terms/concurrent-training/" class="term-link" data-slug="concurrent-training" title="concurrent training">concurrent training</a>, the majority of cycling should occur in Zones 1–2.</p> <h3>Programming Structure for Bodybuilding Athletes</h3> <p><strong>Option A: Separate-day cycling (lower interference, recommended)</strong></p> <ul> <li>Resistance training: 4 days/week (Mon, Tue, Thu, Fri)</li> <li>Cycling: 2–3 days/week (Wed, Sat, optional Sun) as Zone 2 steady-state, 30–45 min</li> </ul> <p><strong>Option B: Same-day cycling (<a href="/terms/intermittent-fasting/" class="term-link" data-slug="intermittent-fasting" title="if">if</a> scheduling demands)</strong></p> <ul> <li>Always perform resistance training FIRST, cycling SECOND (minimum 6 hours gap preferred)</li> <li>If cycling must immediately follow lifting, keep to 15–20 min at Zone 1–2 only</li> <li>Avoid heavy cycling (Zone 4–5) on the same day as lower-body resistance training</li> </ul> <h3>Cycling Duration and Volume Guidelines</h3> <table> <thead> <tr> <th>Hypertrophy Priority</th> <th>Cycling Format</th> <th>Weekly Duration</th> </tr> </thead> <tbody> <tr> <td>Maximum hypertrophy</td> <td>Zone 2 only</td> <td>60–90 min/week</td> </tr> <tr> <td>Balanced development</td> <td>Zone 2 + occasional Zone 4</td> <td>90–150 min/week</td> </tr> <tr> <td>Cardio-focused block</td> <td>Zone 2 + regular intervals</td> <td>150–240 min/week</td> </tr> </tbody> </table> <h3>Technical Considerations</h3> <ul> <li><strong>Saddle height</strong>: Slight knee bend (approximately 25–35 degrees) at bottom of pedal stroke minimizes compressive knee joint stress</li> <li><strong>Cadence</strong>: 80–95 RPM for most training; high cadence (100+ RPM) at low resistance reduces muscular stress but maintains cardiovascular stimulus</li> <li><strong>Resistance setting</strong>: For Zone 2 conditioning, use resistance that produces the target heart rate at 80–90 RPM without pushing against excessively heavy gear (muscular cycling vs. aerobic cycling)</li> <li><strong>Post-cycling nutrition</strong>: Consume carbohydrate-containing meal or snack within 30–60 minutes post-cycling session to restore glycogen before subsequent resistance training</li> </ul>