The global obesity epidemic, affecting over one billion people worldwide, is largely driven by eating behaviors. Appetite, influenced by both intrinsic and environmental factors, plays a crucial role in weight management. A recent study how exercise affects appetite perception in obese males, shedding light on the physiological mechanisms behind hunger suppression post-exercise.

While exercise is well-known for its benefits in weight management, its direct impact on appetite control has remained a subject of debate. Appetite is regulated by a complex network of gastrointestinal and neurohormonal signals, including hormones like ghrelin, leptin, interleukin 6 (IL-6), and neuropeptide Y (NPY). These hormones influence hunger levels, satiety, and energy balance.

The study published in Physiological Reports examines investigated how moderate continuous aerobic exercise (MICE) alters these hormone levels in obese men, ultimately affecting their hunger perception. The findings reveal that certain myokines and cytokines shift dynamically post-exercise, potentially reducing appetite and offering a promising strategy for weight management.

Hormonal Responses to Exercise

The study found that after exercise, there was a significant increase in IL-6 and irisin levels in the exercise group compared to those who remained sedentary. These elevated concentrations persisted for an hour after working out. IL-6 has been associated with regulating metabolism and enhancing fat oxidation, while irisin plays a role in converting white fat into more metabolically active brown fat.

Conversely, the study reported a decrease in neuropeptide Y (NPY) levels, a key neurotransmitter responsible for stimulating appetite. The decline in NPY levels post-exercise suggests a temporary suppression of hunger, supporting the idea that exercise can curb cravings. However, the study did not observe significant changes in IL-7 or leptin levels, two other hormones involved in appetite regulation.

Why Some People Struggle to Lose Weight

Ghrelin, often called the “hunger hormone,” stimulates appetite by increasing activity in specific areas of the brain. Individuals with higher ghrelin levels generally find it harder to lose weight because their bodies signal hunger more frequently.

Research suggests that dieting can lead to an increase in ghrelin levels, making weight loss challenging. Certain medical conditions, such as Hashimoto’s thyroiditis, Prader-Willi syndrome, anorexia nervosa, and bulimia nervosa, are also linked to elevated ghrelin levels, complicating appetite regulation further.

Challenges in Implementing Exercise for Appetite Control

While exercise has clear benefits, the findings should be interpreted with caution. He pointed out that the study had a small sample size, making it difficult to draw definitive conclusions.

Moreover, he highlighted the challenges faced by obese individuals in maintaining an intensive exercise routine. While exercise-induced appetite suppression is promising, consistently engaging in high-intensity workouts may be unrealistic for those who struggle with mobility or fitness levels. More extensive studies are needed to determine the optimal exercise duration and intensity for effective appetite suppression.

Tips to Naturally And Safely Suppressing Appetite

Besides exercise, there are several strategies individuals can use to naturally suppress their appetite and improve satiety:

Increase Protein Intake: Protein-rich foods, such as lean meats, legumes, and dairy, promote feelings of fullness and reduce hunger.

Stay Hydrated: Drinking water before meals can help control portion sizes and prevent overeating.

Opt for Fiber-Rich Foods: Whole grains, vegetables, and fruits high in fiber take longer to digest, keeping you full for longer.

Reduce Simple Carbohydrates and Sugars: Simple carbs and sugars cause rapid spikes and crashes in blood sugar levels, leading to increased hunger.

Prioritize Sleep: Poor sleep disrupts hunger-regulating hormones, making it harder to control cravings.

Manage Stress: Chronic stress increases cortisol levels, which can lead to overeating and weight gain.

The study’s findings indicate that moderate exercise can temporarily suppress appetite by altering key hormones. While more research is needed to refine the details—such as optimal workout duration and intensity—this insight adds to the growing body of evidence supporting exercise as a tool for appetite regulation and weight management.

For individuals looking to curb cravings and maintain a healthy weight, incorporating a well-balanced diet alongside regular exercise remains the most sustainable approach. Future studies focusing on larger populations and long-term effects could provide deeper insights into how exercise can be optimized for appetite control, making it an effective strategy in combating obesity.

Exercise alone is not a magic solution for weight loss, but its impact on appetite hormones presents a promising avenue for managing hunger and energy balance. As research continues to evolve, it becomes increasingly clear that integrating physical activity with mindful eating habits can play a vital role in achieving and maintaining a healthy lifestyle.

A 24-year-old marathon runner, Rachel Apa, collapsed and died two miles from the finish line at the New York City Marathon. In Hyderabad, 36-year-old IBM software engineer Kommineni Gopi died after suffering a heart attack shortly after completing a marathon.

Apa's death was attributed to rhabdomyolysis, a condition involving severe muscle breakdown, while Gopi died following a heart attack.

According to The New York Times, Apa was a former Division I field hockey player at Bucknell University who had trained for months. Gopi was an experienced amateur runner who had undertaken intensive training and multiple endurance runs.

Although such deaths are rare, the incidents highlight the physical demands of endurance running.

How Common Are Deaths During Marathons?

A study published in JAMA, involving 29.3 million US marathon and half-marathon finishers between 2010 and 2023, found:

• Cardiac arrest: 0.54 per 100,000 participants (1 in 185,000).
• Cardiac death: 0.20 per 100,000 (1 in 500,000).

Dr Sudhir Kumar, neurologist at Apollo Hospitals, Hyderabad, said survival has improved with better on-site CPR and defibrillation.

Also read: Water Or Electrolytes? Biggest Hydration Mistakes First-Time HYROX Athletes Make

Who Is At Greater Risk?

According to Dr Sudhir, risk factors include:

• Male sex: Cardiac arrest rates are approximately six times higher in men.
• Older age: Risk rises after 40–50 years.
• Underlying heart conditions: Including coronary artery disease, cardiomyopathy and myocarditis.
• Race distance: Full marathons carry higher cardiac arrest risk than half-marathons.
• Environmental stress: Heat, humidity, dehydration and illness.

Can Extreme Running Affect Heart Health?

Regular running is associated with lower cardiovascular and all-cause mortality and better blood pressure and glucose control.

However, prolonged extreme endurance training may increase the risk of atrial fibrillation, coronary artery calcification in some athletes and myocardial fibrosis in a small subset. These risks remain low for most runners.

What Causes Cardiac Arrest During A Marathon?

Read More: Lancet Study: 1 In 4 Adolescents Worldwide Report No Active Days Every Week: What Are The Health Risks?

Causes vary by age. Younger runners (below 35–40 years):

• Hypertrophic cardiomyopathy
• Arrhythmogenic cardiomyopathy
• Congenital coronary anomalies
• Myocarditis
• Inherited arrhythmias

Middle-aged and older runners:

Coronary artery disease is a major cause and can trigger heart attacks or dangerous heart rhythms.

Other causes include heat stroke, severe hyponatremia, aortic dissection, pulmonary embolism and complicated rhabdomyolysis.

What Is Rhabdomyolysis And Why Is It Dangerous?

Rhabdomyolysis occurs when damaged muscles release myoglobin and potassium into the bloodstream. Excess potassium can trigger dangerous heart rhythms, while myoglobin can damage the kidneys.

Warning signs include severe muscle pain, weakness and dark urine.

“A marathon is not ‘normal’ exercise. It is EXTREME exercise. While most people don’t develop a problem, deaths occur rarely too,” said Dr Rajeev Jayadevan, former president of IMA Cochin.

“Rhabdomyolysis (muscle breakdown) releases potassium into the bloodstream that causes cardiac arrest. Later events include BP crash and kidney shutdown,” he added on X.

Cardiac arrests often occur in the final quarter of a race, near the finish line or shortly after completion.

Why Is Marathon Training Important?

Attempting a marathon without adequate preparation can be dangerous.

“If you are not a trained runner, don't run. Running without understanding the science of it, running without being fit, running without having a baseline health check, running without proper stamina and endurance are all recipes to disaster,” warned Dr Deepak Krishnamurthy, director and lead cardiologist at KIMS Hospital, on X.

People over 40, those with diabetes or hypertension, smokers and individuals with a family history of premature heart disease should consider cardiovascular evaluation before intensive training.

How Can Runners Reduce The Risks?

During training:

• Increase mileage gradually.
• Avoid running during illness.
• Stay hydrated and include recovery days.
• Avoid excessive NSAID use.

• Acclimatise to the weather.
• Start at a manageable pace.
• Hydrate according to thirst.
• Stop for chest pain, fainting, unusual breathlessness or palpitations.

What To Do If A Runner Collapses

• Call emergency services.
• Start CPR if the runner is unresponsive and not breathing normally.
• Use an automated external defibrillator (AED) as soon as possible.

Early CPR and defibrillation can improve survival.

Marathons offer health benefits, but runners need adequate preparation and should recognise warning signs rather than push through them.

With Delhi's air quality nearing 400, doctors have advised people to reconsider their morning workout routines. Outdoor activities such as walking, jogging and cycling can increase exposure to harmful pollutants, particularly when air quality levels are poor.

While regular exercise is important for good health, exercising outdoors when pollution levels are high can affect respiratory and cardiovascular health.

Experts told HealthandMe that adjusting workout timings and choosing indoor alternatives can help reduce exposure.

Delhi's air quality deteriorated to the very poor category on Friday morning, with an Air Quality Index (AQI) reading of 391, just days before Diwali.

Forecasts indicate that the AQI could exceed 400 and enter the severe category between Friday and Sunday, with no immediate relief expected. Around 30 of the 59 monitoring stations across the national capital recorded severe pollution levels on Friday morning, with Rohini reporting an AQI of 475.

Should You Change Your Morning Workout Routine?

Dr Arunesh Kumar, Director and HOD, Pulmonology, Paras Health, Gurugram, told HealthandMe that when AQI levels are high, outdoor activities such as morning walks, jogging and cycling increase exposure to pollutants, particularly because breathing becomes faster during exercise.

Experts recommend moving workouts indoors when pollution levels are high. Yoga, stretching, weight training and low-intensity exercises can help you maintain your fitness routine.

"It's important to check the daily AQI before you go out and to consider moving your exercise indoors when the air quality is poor. You can maintain your exercise regime indoors with yoga, stretching, light strength training and the like. A well-ventilated indoor space is preferable and of course you should avoid doing your exercise near major traffic routes," Dr Arunesh said.

Also read: With Delhi AQI Nearing 400, Pollution & Flu Loom Ahead Of Diwali: What Happens When Both Hit Your Lungs?

What Indoor Exercises Can You Do When AQI Is High?

If air pollution levels are high, you can maintain your fitness routine by moving your workouts indoors. Some alternatives include:

• Yoga: Practise yoga indoors to stay active.
• Stretching: Include gentle stretching exercises in your daily routine.
• Weight training: Opt for indoor strength-training exercises.
• Low-intensity exercises: Choose light workouts that can be done indoors.

How Does PM2.5 Affect Your Health?

"Your breathing rate increases whilst working out, meaning that the pollutants you're breathing can get further into your lungs. This can lead to issues with your breathing and heart over time. Checking your AQI before going on a run/walk/cycle can help create a healthy lifestyle," Dr Rajesh Kumar Gupta, Director, Respiratory Medicine and Interventional Pulmonology, Yashoda Medicity, told HealthandMe.

People with asthma or heart conditions, children and older adults should be particularly careful about exposure on days with high pollution.

Read More: Air Pollution In Delhi: Experts Warn Of Red Eyes, Itching, Watering In Children

How Can You Maintain A Healthy Fitness Routine?

Poor air quality does not mean you need to stop exercising altogether. Experts recommend adapting your routine according to pollution levels.

• Check the AQI: Monitor daily air quality levels before planning outdoor activities.
• Move workouts indoors: Choose yoga, stretching, weight training or other indoor exercises when pollution levels are high.
• Avoid traffic-heavy areas: If you exercise outdoors, avoid major roads and congested areas.
• Stay hydrated: Drink enough water throughout the day.
• Eat a balanced diet: Include fruits, vegetables and whole grains in your meals.
• Prioritise sleep: Get sufficient rest.
• Avoid smoking: Smoking can further affect your health.

Lifestyle choices such as eating a balanced diet, staying hydrated, sleeping well and avoiding smoking support overall well-being, although they cannot prevent the harmful effects of air pollution.

The aim is not to stop exercising but to modify physical activity according to air quality conditions, said the experts. People with respiratory conditions, heart disease, older adults and children should be particularly mindful of their exposure on high-pollution days.

Physical activity is essential for physical and mental health. The World Health Organization (WHO) recommends at least 60 minutes of moderate-to-vigorous physical activity (MVPA) daily for adolescents.

However, a new study has found that one in four (25%) adolescents worldwide – around 240 million young people – reported no active days every week.

An active day is defined as one involving at least 60 minutes of MVPA, including activities that raise the heart rate or breathing rate, such as walking, cycling and sports.

Published in The Lancet Global Health, the global analysis found that adolescent physical activity levels have remained persistently low over the past 15 years.

Key Findings: Adolescent Physical Activity Remains Low

Also read: 24-Year-Old Marathon Runner Dies Before Finish Line Due To Muscle Breakdown: What Is Rhabdomyolysis?

The study analysed 389 population-based surveys from 140 countries and territories, involving 3.2 million adolescents.

In 2025, adolescents averaged just 2.7 active days per week, with only 14% being active every day. The proportion reporting fewer than seven active days has remained unchanged since 2010, and no country is on track to meet the 2030 global target.

Most low- and middle-income regions had higher proportions of adolescents reporting no active days. Some high-income regions recorded small improvements.

The proportion of adolescents reporting no active days ranged from 4% to more than 40% across countries.

Daily activity levels also varied. Finland (28%) and Canada (25%) were above the global average of 14%, while Sweden and Norway stood at 17%, Germany at 13%, France at 11% and Italy at 9%.

"One in four teens worldwide are not active for even one hour on any day of the week. We know this affects their physical and mental health today and for the rest of their lives. We have the power to change this as a society. We can empower teens to be active every day and create inclusive policies to reach that 25% of teens who are not active on any day," said Professor Seth Flaxman from the School of Geography and the Environment, University of Oxford/RPTU University Kaiserslautern-Landau.

Gender Gap: Why Are Girls Less Physically Active?

Read More: Want to Live Longer? Here's How Much Exercise You Should Do

Girls were found less active than boys. Globally, 28% of girls reported no active days, compared with 22% of boys. Only 11% of girls were active every day, compared with 17% of boys. Their weekly average was also lower at 2.4 days, compared with three days among boys.

The study pointed out to restrictive gender norms, safety concerns and a lack of suitable activities as barriers to girls' participation in physical activity.

It calls for gender-responsive programmes and government policies that make schools and neighbourhoods safer and more conducive to physical activity.

What Are The Health Risks Of Physical Inactivity?

Regular physical activity during adolescence helps establish healthy habits that can protect against chronic diseases later in life. Physical inactivity can increase the risk of obesity, heart disease and type 2 diabetes. It can also affect bone development, mental health and cognitive function.

WHO recommends an average of at least 60 minutes of moderate-to-vigorous physical activity daily for children and adolescents.

On the other hand, the benefits include better physical health, improved mental well-being, enhanced learning and educational outcomes, and greater social connection and inclusion in the short term.

Over time, physical activity can lower the risk of noncommunicable diseases, promote healthier adult lifestyles, and improve productivity and quality of life. For the next generation, it can contribute to healthier families, stronger communities and reduced future health burdens.

WHO Calls For Stronger Action

WHO says encouraging adolescents to move more is not enough. Governments must create environments that make physical activity an accessible part of everyday life.

The organisation is calling for action across education, transport, urban planning, sport and health.

"We need to make being active the easy and enjoyable choice. Adolescents need safe routes to walk, cycle, wheel or scoot to school. They need green spaces to explore. They need opportunities to be active throughout the school day, not just in PE," said lead author Dr Tessa Strain from the University of Edinburgh.