In short:
- Regular training raises energy levels and reduces fatigue, even when the training load is moderate.
- Exercise improves the function of mitochondria, the energy factories of your muscles, which helps your cells produce energy more efficiently.
- For lasting strength and longevity, at least 150 minutes of moderate physical activity per week is recommended.
- The energy boost comes from consistency, not from one hard workout.
Training and energy belong together more than many people think: paradoxically, spending energy on movement is exactly what gives you more energy and strength. In this evidence-based overview, we look at why regular exercise reduces fatigue, how your body starts producing more energy at the cellular level, and how much movement you need to feel these benefits for good.
How are training and energy connected?
Training and energy are linked on both a mental and a physiological level. Systematic reviews show that regular physical activity is consistently associated with a greater subjective feeling of energy and less fatigue (Puetz, 2006). This isn’t limited to elite athletes: even in sedentary people with persistent fatigue, moderate aerobic training raised energy levels and reduced fatigue in a controlled trial (Puetz et al., 2008).
If you find it hard to get moving at the start of the season, a structured environment can help. For example, the article Spa&Sport fitness club gives the training season a kick-start describes how a shared start helps you get into a routine. The energy gain from that first step doesn’t come from one hard effort, but from movement becoming a repeated habit.
Why does exercise give you more strength at the cellular level?
The energy in your muscles comes from mitochondria, the energy factories of your cells, which turn food and oxygen into usable energy. Endurance training triggers the formation of new mitochondria (mitochondrial biogenesis), which means your muscles can produce energy more efficiently at the same training load and tire more slowly (Hood, 2009). That’s why, after a few weeks of consistent training, the same walk or flight of stairs feels easier.
Strength training plays a role too: with age, muscle mass and strength decline, a condition the European working group EWGSOP2 calls sarcopenia and links to a higher risk of functional decline (Cruz-Jentoft et al., 2019). Maintaining muscle mass helps preserve everyday strength and independence. You can also read about different forms of training and their effects in the story Striding day at the Reva-Sport fitness club. Training on a treadmill.
How much training do you need for energy?
The American College of Sports Medicine (ACSM) and the World Health Organization recommend that adults do at least 150 minutes of moderate-intensity aerobic activity per week, plus strength exercises for the major muscle groups twice a week (Garber et al., 2011). The WHO also gives the same weekly minimum in its physical activity guidelines, stressing that any movement is better than none (see WHO physical activity guidelines).
The key point is that the feeling of energy builds up gradually. If you start low and increase your training load step by step, you avoid overtraining and reap the benefits without burning out. The topic of nutrition and energy stores is covered in more detail in the article Energy…, and the practical side of sports and nutrition in the story Science in Sport (SiS).
Does training tire you out or give you energy?
In the short term, training uses up energy and can leave you tired for a while, but over the medium term the net effect is the opposite. It is regularity that creates the adaptations that improve circulation, heart function and mitochondrial capacity, all of which help your body use energy more efficiently (Hood, 2009). A gain in energy is therefore an investment: strength and endurance grow over weeks, not hours.
If longevity is your goal, consistent movement is one of the best tools for preserving strength and independence in later life. Training and energy support each other: the more sensibly you move, the more stamina you have left for everyday life.
References
- Puetz TW (2006). Physical activity and feelings of energy and fatigue: epidemiological evidence. Sports Medicine. PMID: 16937952
- Puetz TW, Flowers SS, O’Connor PJ (2008). A randomized controlled trial of the effect of aerobic exercise training on feelings of energy and fatigue in sedentary young adults with persistent fatigue. Psychotherapy and Psychosomatics. PMID: 18277063
- Hood DA (2009). Mechanisms of exercise-induced mitochondrial biogenesis in skeletal muscle. Applied Physiology, Nutrition, and Metabolism. PMID: 19767800
- Garber CE et al. (2011). American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults. Medicine & Science in Sports & Exercise. PMID: 21694556
- Cruz-Jentoft AJ et al. (2019). Sarcopenia: revised European consensus on definition and diagnosis (EWGSOP2). Age and Ageing. PMID: 30312372
Frequently asked questions
Does training really give you more energy?
Yes. Systematic reviews show that regular physical activity is associated with a greater feeling of energy and less fatigue, even in people who were previously sedentary (Puetz, 2006; Puetz et al., 2008).
How long does it take before I feel my energy increase?
The first changes usually appear within a few weeks if you move consistently. Mitochondrial adaptation and improvements in endurance happen over weeks, not hours (Hood, 2009).
How much should I train per week?
The recommended minimum is at least 150 minutes of moderate aerobic activity per week, plus strength exercises twice a week (Garber et al., 2011; WHO).
Is strength training important for energy?
Yes, especially as you age. Maintaining muscle mass and strength helps prevent sarcopenia and preserves everyday strength and independence (Cruz-Jentoft et al., 2019).
What if training leaves me feeling tired?
Short-term fatigue is normal. Start low and increase your training load gradually: over the medium term, the net effect is an energy boost, as long as you avoid overtraining.
Come and train! ArtGym
