How to Build a Strength and Endurance Training Program That Maximizes Both
You do not need to choose between being strong and having good cardiovascular fitness. Most people can improve both at the same time.
The challenge is not whether strength and endurance training can coexist. They can. The challenge is organizing your week so that your important workouts do not consistently undermine one another.
For most people trying to get fitter, a good strength and endurance training schedule includes two to three strength workouts and two to four cardiovascular workouts per week. Hard lower-body workouts should be spaced thoughtfully. Easy cardio can often be combined with strength training. When two demanding sessions fall on the same day, the workout that matters most to your current goal should usually come first.
That is the simple version. The details matter once your goals become more ambitious.
What Is the Interference Effect?
The interference effect is the idea that doing endurance exercise and strength training will lead to opposite adaptations in the muscle, limiting the gains achieved by both exercise types.
This idea is real, but it is often overstated.
Current research suggests that combining aerobic and strength training does not meaningfully prevent most people from building muscle or improving maximal strength. The clearest potential downside appears to be a small reduction in explosive power development, especially when strength and endurance training are performed in the same session. Some studies have also found modest reductions in lower-body strength gains under certain conditions.
There is a physiological reason for the concern. Strength training and endurance training create overlapping but different demands. Strength training places a high priority on force production, neuromuscular recruitment and muscle growth. Endurance training places a greater emphasis on mitochondrial function, oxygen delivery and fatigue resistance.
The body can adapt to both. It simply becomes harder to maximize both at the same time when training volume, fatigue and recovery demands keep increasing.
For a recreational exerciser, the interference effect is rarely a reason to avoid cardio. But it is a reason to plan intelligently. If you are more advanced in your training goals, or have elite goals in either strength or endurance events, it is worth careful planning with a clinician or coach that can help to maximize your goals.
How Many Strength and Cardio Workouts Do You Need Each Week?
Canadian physical activity guidelines recommend at least 150 minutes of moderate-to-vigorous aerobic activity per week and muscle-strengthening exercise at least twice per week.
That is a useful baseline for health, but it is not a perfect prescription if you have performance goals.
For someone training to improve general fitness, body composition and long-term health, I would usually start with:
Two to three full-body strength sessions per week.
Two to four cardiovascular sessions per week.
At least one genuinely easy or recovery-focused day (yoga, sauna, etc).
A simple starting point is two strength workouts and two cardio workouts. Once that feels sustainable, you can add a third strength session, an additional easy aerobic workout or more total training time depending on your priorities.
The updated American College of Sports Medicine resistance-training guidance emphasizes a similar principle: consistency matters more than building an unnecessarily complicated program. Training the major muscle groups at least twice per week is a strong foundation.
More training is not automatically better. A five-day program that you follow for only three weeks is overall less useful for long-term growth than a four-day program that you can maintain for six months. It is not about the amount of training you can fit into a week, it is about how much training you can fit into a month, a year, and a lifetime.
How Should You Structure Your Training Week?
The first rule is to protect your highest-priority workouts. The rest of the program fits around those workouts.
If strength is your main goal, your heavier lifting sessions should happen when you are relatively fresh. Avoid placing a difficult run, cycling interval workout or high-volume leg session immediately before heavy squats or deadlifts.
If endurance is your main goal, protect the sessions that are most important for improving endurance performance. That may be a long run, a tempo workout or an interval session. Do not routinely place heavy lower-body lifting immediately before your hardest run.
Here is a balanced example for someone with equal strength and endurance goals:
Example: Balanced Weekly Training Schedule
Monday: Full-body strength
Tuesday: Moderate-intensity aerobic workout (intervals, tempo)
Wednesday: Full-body strength
Thursday: Easy cardio or rest (Zone 2)
Friday: Full-body strength
Saturday: Longer aerobic workout (45-60 minutes)
Sunday: Rest or gentle activity
This schedule is not magical. It simply distributes the harder work so that you are less likely to arrive at every workout with tired legs.
A more time-efficient option is to combine some sessions:
Monday: Full-body strength + short easy cardio (zone 2)
Tuesday: Rest or walking
Wednesday: Interval or tempo workout + accessory lift (arms + abs)
Thursday: Full-body strength
Friday: Rest or easy cardio
Saturday: Longer aerobic workout
Sunday: Optional strength session or rest
The best schedule depends on your goals, training history, injury history, sleep, work schedule and the types of exercise you enjoy. A downtown Toronto professional training around a busy workweek may need a different structure than someone preparing for a half-marathon or a HYROX race.
Should You Lift Weights Before or After Cardio?
When you have the option, separating demanding strength and endurance workouts is usually the cleaner approach.
Performing them on different days is ideal. When that is not practical, separating them by at least a few hours is reasonable. Research suggests that spacing sessions by at least three hours may reduce the impact on explosive strength development compared with completing both workouts in the same session. Some reviews suggest that a longer gap, such as six hours, may be preferable when schedules allow, but six hours should be viewed as a practical guideline rather than a proven threshold.
When strength and cardio must happen back-to-back, put the higher-priority workout first.
Lift First When:
Building strength or muscle mass is the main priority
The cardio session is easy or moderate and less than an hour
eg. You are planning a short incline walk, easy bike ride or light jog after lifting
Do Cardio First When:
Endurance performance is the main priority
The cardio session is a key workout, such as hard intervals or a long run
You need to perform well during the endurance session rather than simply accumulating aerobic volume
There is no convincing evidence that one sequence is universally best for every goal. A 2024 review found that workout order had small and inconclusive effects on endurance outcomes overall.
In practice, fatigue is often the deciding factor. Heavy squats before running intervals will probably reduce the quality of the intervals. Hard running before heavy squats will probably reduce the quality of the squats. You are not breaking a physiological rule. You are deciding which workout deserves the better effort.
Pair Hard Workouts Carefully
One useful principle is to avoid spreading moderate fatigue across the entire week.
Instead, it actually makes more sense to two high stress workouts on the same day, 4-6 hours apart, and have a double workout day to protect easier recovery days. For example, you might complete a lower-body strength workout in the morning and a moderate length, easy cycling session in the evening, then keep the next day light/ recovery.
Easy aerobic exercise is generally easier to combine with lifting than hard intervals or long runs. Running may also create more lower-body fatigue than cycling, although the research is not perfectly consistent and the real-world impact depends heavily on pace, duration and your training background.
The goal is not to eliminate fatigue. The goal is to spend it deliberately, and make sure you can recover form it.
What If Your Goal Is Simply to Get in Better Shape?
Do not overcomplicate the first step.
Two full-body strength workouts and two or three cardio workouts per week will be enough for many people to make meaningful progress. Build the habit first. Add volume only when your recovery, schedule and goals justify it.
Too many people focus on the details that make 1% difference when they are starting out, rather than focusing on the other 99%. Train hard, train consistently, prioritize recovery, and the rest can come later.
When Is It Worth Seeing a Qualified Healthcare Professional?
A training plan should be challenging, but it should not leave you guessing about whether something is wrong.
It is worth getting assessed if pain is persistent, keeps returning, changes the way you move or stops you from progressing your training. The same applies if one side consistently feels weaker, your performance has dropped without a clear reason or you are repeatedly modifying workouts around the same issue.
A qualified healthcare provider can help determine whether the problem is primarily a programming issue, a recovery issue or something that requires more specific clinical attention. The goal is not to stop you from training. It is to understand the limitation, identify the most important weak points and build a plan that allows you to train with more confidence.
If you are trying to improve both strength and endurance but your training keeps breaking down in the same places, book a functional assessment. We can identify the weak links, clarify what needs attention and help you build a plan that fits your goals.
Frequently Asked Questions
Does cardio prevent muscle growth?
Usually not. Most people can build muscle while performing regular cardiovascular training. Very high endurance volumes, poorly managed fatigue and repeated hard training for the same muscle groups may reduce some adaptations, particularly if muscle growth or power is the primary goal.
Is it better to do cardio and strength training on separate days?
Often, yes. Separate days make it easier to perform both workouts well. When that is not possible, easy cardio can usually be added after lifting without creating a major problem.
How long should I wait between lifting weights and cardio?
A gap of at least a few hours is reasonable when both sessions are demanding. Research suggests that separating sessions by at least three hours may help protect explosive strength adaptations. A longer separation may be useful when practical, especially for higher-level trainees.
Should beginners lift weights or do cardio first?
Beginners should usually prioritize the workout that is most important to their goals. If the goal is general fitness, lifting first and finishing with easy cardio is a sensible default. The bigger priority is creating a schedule that can be followed consistently.
Can I run and train legs during the same week?
Yes. The harder your running becomes, the more carefully you should organize lower-body strength sessions. Avoid placing your heaviest leg workout immediately before your most important run.