The Aerth Journal

Back to fitness: how to restart and make it last September has something special. It’s not the start of the year in the calendar sense. It’s the time when we put away our summer habits and decide, once again, what we want to build. For many, the back-to-fitness season feels like a promise made to oneself. Sometimes kept. Often postponed. Not for lack of willpower, but because we go about it the wrong way. We start again too hard, too fast, without structure. And three weeks later, the routine collapses under the weight of busy schedules and accumulated fatigue. This guide isn’t here to motivate you. Motivation is fleeting and unreliable. It is here to help you build something more solid: a discipline that holds up, even when you don’t feel like it. Understanding why restart attempts fail Before talking about method, we must understand the mechanism of failure. The majority of fitness restarts collapse for the same reason: the gap between initial ambition and daily reality is too wide. We commit to 4 sessions a week in September when we didn’t do any in August. We go back to March’s intensity levels when the body has deconditioned. We rely on the motivation of the moment—naturally high at the start of the season—without building the automatic habits that will take over when that motivation fades. A habit is not built through willpower, but through repetition in a stable context. It is not the intensity of the effort that creates the routine; it is its regularity. Honestly assessing your starting point The first step is not to choose an activity or buy a membership. It is to conduct a lucid assessment of your current state. What the summer break has actually changed: After 3 to 4 weeks without training, VO2max decreases by 5 to 10%. Muscular strength is better maintained—about 4 to 6 weeks before a significant loss—but endurance and cardiovascular capacity decline faster. Tendons and ligaments take longer to recondition than muscles—this is where most restart injuries occur. The two-thirds rule: for a healthy restart, start at about two-thirds of your usual volume and intensity. Not for a lack of ambition—but for body intelligence. The first three weeks serve to recondition connective tissues and reactivate motor patterns. Performance will naturally return thereafter. Choosing your activity: the question we ask wrongly We often look for the perfect activity—the one that burns the most calories, improves cardio the best, or is the most trendy. That is the wrong question. The right question is: what activity will you still be doing in six months? Proximity Studies on athletic behavior show that the distance between home and the training location is one of the best predictors of dropout. Beyond a 20-minute commute, the regularity rate drops significantly. Choosing a gym or a route that is a 10-minute walk away isn’t a concession—it’s a strategy. Social anchoring Training with someone else—a partner, a group, a coach—doubles or triples the likelihood of maintaining a practice for 6 months. Not because it’s more motivating, but because it creates an external obligation that takes over when internal motivation is absent. Immediate pleasure Contrary to what we believe, long-term benefits—weight loss, longevity, performance—are poor behavioral drivers. What creates the habit is the pleasure felt during or just after the session. Choose an activity you enjoy doing, not just one you would like to have done. Building a routine that sticks: the method 1. Start small, really small The main enemy of regularity is setting the bar too high. A 25-minute session three times a week, maintained for 8 weeks, is infinitely better than 5 one-hour sessions for 10 days followed by quitting. The concept of a "minimum viable workout" is well-documented in behavioral psychology: set a threshold so low that it becomes difficult not to do it. 20 minutes of running. 3 sets of strength training. The goal is not performance—it is not breaking the chain. 2. Associate training with an existing anchor Habits are not created in a vacuum—they are grafted onto already automatic behaviors. This is what researchers call "habit stacking": associating the new habit with something that already exists in your daily life. "On Monday at noon, I do my session before lunch." The phrasing matters: it anchors the habit in a precise context, not in a vague intention. 3. Schedule the session, not the intention Blocking time in your calendar to "do some exercise this week" does not work. What works is blocking a precise, recurring, non-negotiable slot—like a professional appointment. Tuesday at 7:00 AM. Thursday at 12:30 PM. Saturday at 9:00 AM. The precision of the slot reduces decision fatigue. And every decision avoided is one less source of resistance. 4. Anticipate obstacles, don't ignore them Most routines collapse not for lack of willpower, but because a foreseeable obstacle was not anticipated. Busy week, work trip, weather, fatigue.The "if/then" approach: for every likely obstacle, prepare a response in advance. "If I get home late on Tuesday, then I will do a short session at home instead of skipping it.""If it rains, then I will replace the run with 30 minutes of indoor strength training." This isn’t flexibility; it’s preparation. 5. Measure regularity, not performance In the habit-building phase, performance, times, weights, and measurements are the wrong indicators. The right indicator is regularity: how many sessions over the last four weeks? A simple calendar where you tick off each completed session creates a powerful momentum effect. The goal becomes not to break the streak, which proves to be a far more reliable behavioral driver than performance goals. The outfit as a mental signal This point is often overlooked, yet documented in psychology: what you wear influences how you behave. This is what researchers call "enclothed cognition," the effect of clothing on the mental state. Putting on an outfit you feel good in—an adjusted, sober, suitable outfit—isn't just an aesthetic detail. It is a signal sent to yourself. A ritual of transition between daily life and effort. For someone looking to establish a routine, this ritual counts. AERTH pieces designed for the back-to-fitness season: gear that lasts The return from summer is often an opportunity to renew your gear. But impulse buying—a flashy outfit, the latest pair of shoes—rarely creates a lasting relationship with what you wear. At AERTH, the approach is the opposite: pieces designed to last through the seasons without aging, both aesthetically and technically. Made in Portugal and Oeko-Tex certified, they accompany a gym strength session just as well as an early morning run—without ever betraying their purpose with an intrusive logo or a fit that doesn't hold up after washing. The idea is not to have an outfit for every activity. It is to have the right pieces—the ones you stop thinking about, because they simply do what they need to do. Sober, precise, silent. Just like the practice they accompany. The mindset: build, don't restart There is an important distinction between restarting and building. To restart is to pick up where you left off, with the same ambition, the same plan, and often the same result. To build is to accept that a restart is a starting point—not a step backward—and to lay the foundations for a practice that doesn't need motivation to exist. The athletes who last in the long run are not those who are the most motivated. They are those who understood that discipline is a skill that is trained—and that every session, even an imperfect one, is a repetition of that skill. In summary: the seven principles of a lasting fitness restart Start at two-thirds of your usual level, without exception. Choose the activity you will still be doing in six months, not the one you think you "should" do. Set precise, non-negotiable slots in your schedule. Start small—regularity trumps intensity. Graft the new habit onto an existing behavior. Anticipate obstacles with "if/then" responses prepared in advance. Measure sessions completed, not performance. The back-to-fitness season is not a promise. It is a decision. Make it once, then let the structure do the rest.

Women's sportswear: a guide to combining style and performance There is a persistent misconception in sportswear: that performance and elegance are two opposing requirements. That one must necessarily come at the expense of the other. That a truly technical outfit cannot be beautiful, and that a beautiful outfit cannot be truly technical. That is false. And the way we dress to train deserves better than that compromise. What you wear changes the way you train It is not a question of vanity. It is neuropsychology. In 2012, researchers Adam and Galinsky formalized the concept of "enclothed cognition": the clothes we wear directly influence cognitive processes and behavior. In other words, what we wear changes the way we think, and therefore the way we act. In a sports context, the implications are concrete. An outfit that feels good, fitted, understated, and adapted to the effort, amplifies self-confidence and the level of engagement. Conversely, an uncomfortable outfit creates a constant distraction: you think about what is pulling, what is slipping, what is see-through, instead of thinking about the effort. A good outfit is not noticeable. It fades away to make room for what matters. Materials: where it all really happens Before the cut, before the color, before everything, comes the material. It determines whether a piece will keep its promises during exercise, after 50 washes, and in two years' time. Polyamide: the benchmark in technical sportswear. Soft against the skin, naturally stretchy, resistant to abrasion and repeated wash cycles. It is the foundation of any serious garment. Elastane: always used to complement polyamide, at 15 to 20%. It ensures the fabric snaps back after every movement, which determines if your leggings will hold their shape after six months of wear. Recycled materials: rPA, rPET. They offer technical performance comparable to virgin materials, with a reduced environmental footprint. A relevant criterion for pieces designed to last. What to avoid 100% Cotton: it absorbs perspiration, gets heavy during exercise, and takes a long time to dry. Low-end polyester: it retains odors, loses its shape quickly, and pills after a few washes. Acrylic: it is not breathable and has a very short lifespan for sports use. Grammage: concrete benchmarks Running or gym leggings: 220 to 280 GSM to guarantee opacity and muscle support. Tops and tank tops: 160 to 220 GSM to maintain lightness and breathability. Leggings under 200 GSM will almost systematically have issues with transparency in a squat position or while running, regardless of their color. Running: choosing your running outfit with precision Running is the most demanding discipline for textiles. Every detail counts over time, and the flaws of a poor piece are revealed mile after mile. Leggings or shorts: the right logic for choosing Below 15°C (59°F), leggings are essential. They maintain muscle warmth and reduce the risk of strain on long runs. Above 20°C (68°F), shorts take over for lightness and ventilation. In between, it is a matter of personal preference and the intensity of the effort. For running leggings, four non-negotiable criteria: Guaranteed opacity: minimum 240 GSM, tested in a squat position. Flat seams: essential to avoid chafing over long distances. High waist: it stabilizes the pelvis and eliminates constant adjustments. Light compression: it improves proprioception and venous return during prolonged efforts. The running top A running top or tank top must wick away perspiration, not absorb it. An absorbent material becomes heavy during exercise and prolongs the feeling of moisture on the skin. A technical material with rapid wicking transports sweat to the outside of the fabric so that it can evaporate. Breathable inserts on the back and under the arms are not aesthetic details. They are active ventilation zones. The gym: HIIT and muscle strengthening, two different approaches People often confuse the two. Yet their technical requirements are distinct. For HIIT HIIT generates intense perspiration in a short time, with explosive and multidirectional movements. The priorities are clear: maximum lightness, rapid wicking, total freedom of movement. A lightweight technical short paired with a breathable tank top is the most effective combination. Avoid compression pieces that limit range of motion or generate excessive heat. For muscle strengthening Strengthening requires a different approach. Light compression improves proprioception, awareness of the body's position in space, which is directly useful for technical exercises like squats, deadlifts, or hip thrusts. Long high-waisted leggings stabilize the pelvis and support heavy loads. A fitted T-shirt allows you to observe alignment in the mirror, which is not trivial when technique determines performance and injury prevention. Common criteria for both practices: Friction resistance: bars, machines, and mats stress fabric differently than running. Guaranteed opacity in all positions: floor exercises and squats are unforgiving. Waistband stability: it must not slide down during exercise, regardless of the range of motion. Elegance as a technical criterion: the codes that structure an outfit Elegance in sportswear is not about the superficial. It is about coherence between the garment, the body, and the movement. And it relies on precise choices. The color palette Start with a neutral base: black, charcoal gray, navy, beige, off-white. These shades naturally coordinate with each other, transcend the seasons, and do not age. A color accent can be used, but it is best kept minimal. Coordinated sets Leggings and a top in the same material or color immediately create a structured silhouette. It is one of the most effective codes of premium sportswear, and one of the simplest to apply. The fit Neither too tight nor too loose. A well-fitted cut follows the lines of the body in motion without restricting. A garment that is too loose loses its sharpness; a garment that is too tight highlights the effort rather than accompanying it. The finishes Invisible flat seams, discreet or absent logos, clean edges: these are the details that distinguish a durable piece from one that is forgotten after a few months. They aren't seen, which is precisely why they matter. The gym-to-street transition A well-chosen outfit goes through the day effortlessly. The key: pieces with refined finishes, an understated palette, and cuts that don't shout about their intended use. Technical leggings in a neutral color paired with a bomber jacket or trench coat become something more than just gym wear. AERTH pieces: where durability meets elegance At AERTH, our stance is simple: pieces designed to last, both technically and aesthetically. Made in Portugal and Oeko-Tex certified, they meet the requirements of performance without sacrificing visual coherence. No intrusive logos. No trend-chasing. Meticulous cuts, materials selected for their longevity, and colors that integrate into a wider wardrobe. The elegance of a technical outfit is precisely this: that you forget you are wearing it, so you can better focus on what matters. FAQ Which women's sportswear should I choose to start running? High-waisted polyamide-elastane leggings, at least 220 GSM, and a technical quick-wicking top form a solid foundation. Prioritize flat seams and a stable waistband. How can I build an elegant women's sports wardrobe without multiplying it infinitely? Invest in three to four quality pieces rather than ten mediocre ones. Neutral colors and fitted cuts multiply the possible combinations. Leggings or shorts for summer running? Above 20°C (68°F), shorts are better for lightness and ventilation. Below that, leggings remain more comfortable and protect muscles better. What is the concrete difference between a HIIT outfit and a muscle strengthening outfit? For HIIT, lightness and sweat wicking are the priority. For strengthening, light compression, waistband stability, and guaranteed opacity are key. How should I care for my sports clothing to make it last? Wash at a maximum of 30°C (86°F), without fabric softener and without using a tumble dryer. Air drying preserves the fabric's elasticity and fit in the long term.

Training in the summer: the technical guide to performing without injury. Summer does not put training on hold. It reveals it. When the heat sets in, the temptation is great to slow down, to postpone, to wait for more temperate conditions. But those who move with intention know that it is precisely in these moments that consistency takes on its full meaning. Training in the summer means learning how to work with the elements — not to endure them, but to understand them in order to better integrate them into your practice. Heat and performance: what really happens in the body Before adapting your training, you must understand what heat does physiologically. As soon as the outside temperature exceeds 25°C, the body activates its thermoregulation mechanisms: it sends more blood to the skin to dissipate heat, to the detriment of the muscles. The direct consequence: for an identical effort, the heart rate increases by 10 to 20 bpm. What you were doing in Zone 2 at 15°C mechanically becomes Zone 3 at 30°C — without you having changed anything in your pace. This is the first trap of summer training: relying on your usual benchmarks when the parameters have changed. Acclimatization: the 14 days that change everything The human body is remarkably adaptable — but this adaptation takes time. It takes an average of 10 to 14 days of progressive exposure to heat for physiological adaptations to truly take hold. Plasma volume increases by 3 to 5%, which improves oxygen transport and facilitates thermoregulation. The body begins to sweat sooner and more efficiently, anticipating the rise in temperature. The heart rate for a given effort gradually drops back toward its usual values. What this implies in practice: the first two weeks of heat are not meant for performance. They are for acclimatization. Reducing intensity by 15 to 20% during this period is not a concession — it is an investment. Guiding your effort by heart rate, not by sensations In summer, subjective sensations are deceptive. Heat creates a diffuse fatigue that distorts the perception of effort. The best tool then becomes heart rate — or better yet, heart rate reserve. The practical rule: in high heat, lower your target zones by 5 to 10 bpm. If your usual Zone 2 is between 140 and 155 bpm, aim for 130 to 145 bpm during heat waves. The cardiovascular adaptation will still occur — without the risk of overtaxing the system. Shifting sessions to before 9 am or after 7 pm is not just a question of comfort. It is a performance decision: the temperature can vary by 8 to 12°C between the middle of the day and early morning, which radically changes the actual load imposed on the body. Hydration: beyond "drinking enough" Summer hydration is misunderstood. Drinking large quantities of water is not enough — and can even become counterproductive. The weigh-in test is the most reliable tool to calibrate your actual needs: weigh yourself before and after the session. Each kilogram lost corresponds to about 1 liter of fluid to be replenished. A loss of more than 2% of body weight leads to a measurable drop in cognitive and physical performance. Beyond 3%, the risk of heatstroke becomes serious. The hyponatremia trap Drinking too much water without sodium dilutes the salt concentration in the blood. This phenomenon, hyponatremia, causes nausea, cramps, and headaches — and is often confused with dehydration, leading one to drink even more. For sessions exceeding 60 to 75 minutes, reintegrating electrolytes — sodium primarily, followed by magnesium and potassium — is not an option; it is a physiological necessity. Concrete benchmarks: 500 ml of water in the 2 hours preceding the effort. 150 to 200 ml every 15 to 20 minutes during the effort. For long sessions: 400 to 800 mg of sodium per liter of fluid. After the effort: 1.5 liters of fluid per kilogram lost, spread over 2 to 3 hours. Water is not an accessory. It is the first gesture of performance. Summer recovery: the window most miss Heat slows down muscle repair processes — the body mobilizes part of its resources to thermoregulate, to the detriment of tissue reconstruction. Recovering in summer therefore requires more attention, not less. The 30-minute metabolic window In the 30 minutes following an effort, muscles are in a state of maximum nutrient uptake. This is the moment when protein and carbohydrate intake is most effectively used for recovery. Aiming for 20 to 30g of protein combined with moderate glycemic index carbohydrates in this window significantly accelerates glycogen resynthesis and muscle reconstruction. The choice of protein is not trivial: whey proteins are ideal in this post-effort window thanks to their rapid absorption. Casein, which is slow-digesting, is more relevant before bed to support nocturnal reconstruction. Contrast bathing rather than just a cold shower A cold shower after effort is common — but contrast bathing, alternating hot and cold, is documented as being significantly more effective at reducing inflammatory markers and delayed-onset muscle soreness. The recommended protocol: 1 to 2 minutes in hot water (38 to 40°C), then 1 minute in cold water (10 to 15°C), repeated for 3 to 4 cycles. The alternation creates a vascular pump effect that accelerates the elimination of metabolic waste. Sleep: the most underestimated variable It is at night that the body produces most of its growth hormone — and therefore when muscle reconstruction actually happens. Heat often degrades the quality of deep sleep. A few concrete adjustments: bedroom temperature between 17 and 19°C, exposure to natural light in the morning to regulate the circadian cycle, and avoiding intense effort in the 3 hours before bed. High post-exercise body temperature delays sleep onset. AERTH pieces designed for summer: when the material becomes performance Equipment is not neutral. In hot weather, what you wear directly determines the quality of your effort — and your ability to prolong it. At AERTH, every piece is designed around one principle: that the garment should never be what you are thinking about during the effort. The selected materials offer maximum breathability, wick away moisture without weighing you down, and maintain their shape after every session. The technical t-shirt relies on a dual-material construction designed for summer conditions: a light front that does not restrict movement, and a micro-perforated back that dissipates heat — so that nothing you wear gets between you and your effort. Manufactured in Portugal and Oeko-Tex certified, AERTH creations are designed to last — in their construction as well as their aesthetic. No intrusive logos, no passing trends. Simple, subtle, silent pieces. The ones you come back to season after season because they do what they promise, without doing anything more. The elegance of technical clothing is exactly that: forgetting you are wearing it, so you can better focus on what counts. Mindset: the quiet discipline of summer There is something special about someone who trains in July, without an audience, without a near competition, without visible outside pressure. This is where the true nature of a practice is revealed. Summer training is not measured by records. It is measured by the quiet constancy of the person who returns, again and again, because they have understood that the elegance of a practice is built in these moments — when no one is looking. In summary: the golden rules of summer training Accept the first 14 days as an acclimatization phase, not a performance phase. Guide your effort by heart rate, not by sensations. Train before 9 am or after 7 pm to limit thermal load. Weigh yourself before and after the session to calibrate your hydration needs. Reintegrate electrolytes after 60 minutes of effort. Take advantage of the 30-minute post-effort window for recovery nutrition. Prefer contrast bathing to just a cold shower. Protect your sleep quality — that is where everything is rebuilt.

The best coffee shops after a run in Paris Paris is running more and more. Along the Canal Saint-Martin, on the banks of the Seine, or around the Bois de Vincennes, running has become much more than a sport: it’s an urban ritual. And for the past few years, another habit has accompanied these morning kilometers: the coffee run. Running, slowing down, grabbing a coffee, meeting up with friends, extending the momentum in a different way. Halfway between sport and lifestyle, this "run & coffee" culture is gradually transforming the way Parisians experience their athletic practice. Here are some of our favorite coffee shops for extending a run in Paris. Ten Belles — Canal Saint-Martin If one had to summarize the spirit of the Parisian coffee run, Ten Belles would probably be one of the first places to mention. Located a few minutes from the Canal Saint-Martin, the café has become the perfect spot after a morning outing in Eastern Paris. The atmosphere is simple, bright, and lively, with a clientele of creatives, runners, and neighborhood regulars who come as much for the coffee as for the vibe. To order: a flat white and still-warm banana bread. Café Kitsuné — Palais Royal Calmer and more minimalist, Café Kitsuné offers a soothing interlude in the heart of Paris. After a few kilometers between Concorde, the Tuileries, and the banks of the Seine, the Palais Royal garden becomes an ideal place to slow down the pace. The discreet elegance of the venue resonates perfectly with this new generation of urban athletes who seek balance as much as they seek movement. To order: a cortado and a slice of carrot cake. Dreamin Man — 11th Arrondissement More intimate, Dreamin Man attracts a loyal clientele that loves the coffee as much as it loves quiet places. It’s the type of place you head to after a long run in Eastern Paris, when the city is gently starting to wake up. The atmosphere is slower, almost introspective, perfect for extending that moment of mental clarity that running often provides. To order: a cappuccino and the cake of the day. Bonjour Jacob — Saint-Germain-des-Prés Nestled on a quiet street in Saint-Germain, Bonjour Jacob is the kind of address you head to after a slow run along the banks of the Seine. The atmosphere is soft and bright, with a few sidewalk tables. The place attracts a very Parisian clientele: neighborhood regulars, freelancers, young parents, and, of course, runners. To order: an iced latte and the Turkish eggs. Noir Coffee Shop — Haut Marais More urban and more dense, Noir fits perfectly into the rhythm of the Marais. You’ll encounter as many freelancers as runners or cyclists who have come to recover after a morning session. The place embodies this new Parisian athletic culture well: less focused on pure performance, more on energy, movement, and everyday life. It’s the perfect spot after a short pre-work run, an urban run between Bastille and République, or for a quick coffee after a hybrid workout. To order: an espresso tonic in the summer and the grilled cheese. Why are coffee runs so appealing? The success of coffee runs says something broader about our relationship with sports. For a long time, running primarily meant performing, improving, and optimizing. Today, many are looking for something else: balance. A breath of air in days that are often too fast-paced. Running thus becomes a social, aesthetic, and almost meditative moment. We run to move, to see the city differently, to meet up with friends, or simply to start the day with more energy. The coffee extends that moment. The coffee run wardrobe This new way of practicing sports is also changing how we dress. Outfits are becoming more versatile: technical yet elegant pieces, comfortable materials, and cuts designed as much for movement as for the city. Sportswear is gradually leaving the gym to become part of everyday life. At Aerth, we design clothing intended to accompany this contemporary movement: running, walking, traveling, slowing down — without ever having to choose between performance and aesthetics. You can enjoy and discover the new AE Series collection right here.

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