Skip to content
Artwork for DFW Running Talk
SportsRunning

DFW Running Talk

Chris Detzel

"DFW Running Talk" is a podcast dedicated to the vibrant running community in the Dallas/Fort Worth metroplex. Each episode features in-depth conversations with local running experts, including coaches, athletes, race directors, and dieticians. We explore training tips, upcoming events, nutrition advice, and inspiring stories from the DFW running scene. Whether you're a seasoned marathoner or a casual jogger, tune in to connect with and learn from the diverse voices shaping our local running culture.

Play
  • 21 episodes
  • weekly
  • Avg 44 min
  • English
Counted on this page — what you have heard stays on this device, so it is not something the list can be paged by.
  • #132
    Monday · 26 min

    Chasing a Sub-3 Marathon After a Life-Changing Crash

    Barely able to walk after a car crash. Now chasing a sub-three-hour marathon. This is a story about rebuilding, finding community, and giving the next starting line everything you have. From living in a car in Los Angeles to a 3:25 Dallas Marathon debut, this journey has taken some unexpected turns—including accidentally running a half marathon and completing a 33-mile run from Dallas to Fort Worth. We explore the lessons from hitting the wall at mile 23, how running friends help build consistency, and what’s different heading into the Indianapolis Marathon. The conversation closes with the crash that forced everything to stop—and the gratitude that followed. CHAPTERS 00:00 The road to marathon number two 05:09 Living in a car and finding a new direction 10:05 Finding community through Dallas running clubs 15:11 A 3:25 marathon debut and lessons from the wall 24:23 Preparing for Indianapolis 26:15 A 33-mile Dallas-to-Fort Worth run 29:53 Chasing sub-three 31:05 The crash, recovery, and gratitude Find free training plans, races, and running resources: https://www.dfwrunningtalk.com Get the Monday DFW Running Email: https://dfwrunningtalk.substack.com Looking for a 5k, 1/2 marathon or full marathon training plan? https://dfwrunningtalk.com/training-plans Find most races in all of Texas: https://dfwrunningtalk.com/races Follow DFW Running Talk and leave a rating if this story resonates with you.

    • Transcript
  • #131
    September 28 · 48 min

    From a Five-Minute Run to Kilimanjaro: Building Endurance and Confidence

    Cheryl Haynes’s first run lasted five minutes. Her goal was to climb Mount Kilimanjaro. What followed was a journey through mountain summits, setbacks, a first marathon, and finding comfort in running after losing her mom. In this episode of DFW Running Talk, Cheryl joins host Chris Detzel to share how she built endurance as a beginner in flat South Florida, prepared for Kilimanjaro and Mont Blanc, and returned to summit Aconcagua after an unsuccessful first attempt. We explore the mental side of endurance, the lessons that came from starting small, and how a welcoming DFW running club became something Cheryl looks forward to each week. It’s a story for anyone wondering whether they’re capable of more—even if a single mile feels far away. What’s one running or adventure goal you once thought was out of reach? Explore free training plans, races, running clubs, and coaches: https://www.dfwrunningtalk.com Get the Monday DFW Running Email: https://dfwrunningtalk.substack.com Follow DFW Running Talk for more real stories from the running community.

    • Transcript
  • #130
    September 21 · 1 hr 5 min

    From Running Burnout to Winning the Leadville 100

    Burnout and injuries pushed her away from running. Years later, Jacquie Mannhard became the women’s Leadville 100 champion. This is an honest conversation about rebuilding a relationship with running—and discovering that your best performances might still be ahead. We explore the pressure of collegiate running, underfueling, returning to competition after children, and the confidence it takes to line up against elite ultrarunners. Hear how changes to fueling, cross-training, and mindset shaped her comeback and helped her win Leadville in 2023. Then follow her return in 2026, when a battle through mile 95 produced a second-place finish she treasures even more than her victory. Whether you’re recovering from a setback, considering your first ultramarathon, or trying to find joy in training again, this story will give you plenty to think about. CHAPTERS 00:00 Meet a Leadville 100 champion 12:06 Collegiate running, underfueling, and burnout 19:53 Stepping away and rebuilding 31:52 Returning to running after children 41:47 Coaching and learning to believe 49:18 Injury recovery and rethinking fueling 55:23 Winning the Leadville 100 1:03:19 Masters running and the fight for second place Follow DFW Running Talk on Spotify so you never miss an episode. Enjoyed the conversation? Leave a rating and tell us: What helped you find your way back to running? Get the Monday DFW Running Email: https://dfwrunningtalk.substack.com/ Explore training plans, races, running clubs, and coaches: https://www.dfwrunningtalk.com/

    • Transcript
  • #129
    September 14 · 48 min

    A 31-Hour Double Iron Triathlon—and a Life of Adventure

    A double iron-distance triathlon. 31 hours and 31 minutes. Discover the story behind the finish—and a life built around adventure. Before becoming a Fit 4 Adventure co-owner, this Texas athlete spent years caddying on professional golf tours and finding races wherever work took her. She shares stories from a Double Anvil finish and extreme triathlons in Alaska and Iceland, plus the weekly swim, bike, and run challenge that keeps her active today. We explore Boston Marathon travel, turning a destination race into a vacation, and choosing adventures that match your fitness. Along the way, a trip planned for friends becomes the beginning of a new career—and lasting community. CHAPTERS 00:00 Growing up active in Texas 07:12 Life as a professional golf caddie 15:56 A weekly challenge to keep moving 18:07 The 31-hour double iron-distance triathlon 25:54 Boston Marathon travel and race weekend 30:37 Running and exploring Iceland 38:25 From golf to owning an adventure travel company 47:37 Choosing your next race vacation or adventure FEATURED COMPANY Fit 4 Adventure Follow DFW Running Talk on Spotify or Apple Podcasts so you never miss an episode. Rate the show to help more runners discover these conversations. What race would you build a vacation around? Leave a comment. DFW Running Talk — the stories behind Dallas–Fort Worth’s runners. Running resources: https://www.dfwrunningtalk.com/ Newsletter: https://dfwrunningtalk.substack.com/ YouTube and Instagram: @dfwrunningtalk

    • Transcript
  • #128
    September 7 · 59 min

    Two Marathon Blowups to 2:36

    A Dallas–Fort Worth runner turned two marathon blowups into a 2:36:11 breakthrough at Houston. This DFW Running Talk runner interview reveals what changed in his marathon training—and why it took more than fitness. Kevin Barr returned to running in 2023 after nearly seven years away. His first marathon ended in a painful 3:10. He tried again, bonked again and finished in 3:02. Kevin eventually broke three hours with a 2:57, joined Completely Sloth and began training with some of the fastest runners in DFW. At the Houston Marathon, he caught the women’s Olympic Trials qualifying pace group, negative-split the race and finished in 2:36:11. Kevin explains how he: • Increased his mileage and consistency • Learned from two marathon blowups • Changed his pacing to finally break three hours • Used faster training partners to reach another level • Balances nine to ten hours of training with work and four children • Plans to chase a 2:29 marathon next Know a runner we should interview? Send your suggestion at https://dfwrunningtalk.com.

    • Transcript
  • #127
    August 31 · 51 min

    How to Qualify for the Boston Marathon: The Training Behind a 2:45

    Running coach Rafa Aguilar explains how he quit vaping, went from throwing up after his first 5K to running a 2:45 Houston Marathon, and earned a Boston Marathon qualifying time in less than three years. Rafa shares the marathon training, strength work, fueling plan, running community and negative-split pacing strategy behind his transformation—including how he saved his hardest effort for the final 10K and closed Houston with sub-six-minute miles. Follow Rafa at @rafarunz and discover more Dallas–Fort Worth running stories at https://dfwrunningtalk.com.

    • Transcript
  • #126
    August 24 · 56 min

    3:27 to 2:23 at the Boston Marathon

    David Slear shares the training, mileage, and racing decisions behind his 64-minute transformation. David traces his journey from Princeton lightweight rowing through triathlon and into competitive marathon running. We discuss the fueling mistake that destroyed his first Dallas Marathon, how the DFW running community gave him confidence to chase faster times, and what changed when he began running more than 100 miles per week. David also explains why he uses two-a-day runs, how he balances training with work and family, and why he races by effort instead of locking onto a specific pace. Whether you’re chasing a Boston qualifier, building marathon mileage, or trying to break through a plateau, this conversation offers an honest look at what major improvement requires. CHAPTERS (00:00) Meet 2:23 marathoner David Slear (13:38) The 3:27 Dallas Marathon blowup (24:35) Finding the DFW running community (27:29) Winning his second marathon in 2:39 (44:00) Building toward 110-mile training weeks (47:43) Running 2:28:41 at the Chicago Marathon (52:05) Breaking the rules at the Boston Marathon (1:01:23) Self-coaching, two-a-days, and staying healthy Follow DFW Running Talk on Spotify or Apple Podcasts so you never miss an episode. Rate the show—it’s one of the biggest ways you can help new runners find us. Know a DFW runner we should interview? Send us your recommendation. DFW Running Talk—the stories behind Dallas–Fort Worth’s runners. dfwrunningtalk.com · YouTube · Instagram · Substack

    • Transcript
  • #125
    August 17 · 52 min

    Stuck at 2:58 for a Decade—Then a 2:37 Marathon

    The former TCU runner, CFO, and father of two explains how he progressed from a 3:28 marathon debut to a Boston qualifier—and ultimately one of the strongest races of his life. We get into the marathon training volume that changed everything, why 55–60 miles per week wasn’t enough for his goals, how the DFW Sloths pushed him toward 70–90-mile weeks, and the race-day pacing decision that saved his CIM. Jeff also shares what runners chasing a sub-3-hour marathon, Boston qualifier, BQ, or major marathon PR can learn from his long plateau: improvement comes from patience, community, fueling, recovery, and years of consistent work. (00:00) Jeff Pels and the long road to 2:37 (12:25) From a 3:28 debut to a sub-3 Boston qualifier (17:24) What finally broke the 2:58 marathon plateau (22:44) Increasing from 55 to 90 miles per week (28:38) How the DFW Sloths made him faster (33:37) Rebounding from a difficult Boston Marathon (38:06) The race strategy behind his 2:37 at CIM (50:18) Patience, community, and long-term improvement Follow DFW Running Talk on Spotify or Apple Podcasts so you never miss an episode. Rate the show—it’s one of the biggest things you can do to help new runners find us. Know a DFW runner we should feature? Send us a message at chris@dfwrunningtalk.com. DFW Running Talk—the stories behind Dallas–Fort Worth’s runners. https://dfwrunningtalk.com https://youtube.com/@DFWRunningTalk https://instagram.com/dfwrunningtalk https://dfwrunningtalk.substack.com

    • Transcript
  • #124
    August 10 · 48 min

    Curvy Girl Running Building Confidence and Community with Kai Michelle

    Kai Michelle, founder of Sweaty and Steady Curvy Girl Run Club, joins DFW Running Talk to discuss beginner running, body confidence, marathon training, and building an inclusive women’s running community in Dallas. Kai shares how she went from completing casual 5Ks to training for the BMW Dallas Half Marathon, documenting her journey through the Curvy Girl Running Chronicles, and inspiring women who never considered themselves runners. That momentum eventually became Sweaty and Steady—a Dallas run club created for curvy women, slower runners, run-walkers, and anyone who has ever felt left behind. In this conversation, Kai explains why pace-inclusive run clubs matter, how running can support women through major life changes, and what it takes to create a safe and encouraging fitness community. She also talks about running with Strava during New York City Marathon weekend, preparing for her first full marathon, and celebrating every runner from the front of the pack to the final finisher. This episode is for beginner runners, back-of-the-pack runners, women interested in running, and anyone searching for running motivation or a supportive Dallas run club. Learn more at www.DFWRunningTalk.com.

    • Transcript
  • #123
    August 3 · 49 min

    She Thought One Mile Was Too Far—Then Ran a 2:57 Marathon

    Kaitlin Moore once believed running a mile was too far. Years later, the former Division I soccer player, working mom of three, and Dallas-area runner crossed the Houston Marathon finish line in 2:57. Kaitlin joins Chris Detzel on DFW Running Talk to share how she went from casually running to completing her first marathon in 3:27, qualifying for Boston, running 3:08 in Houston, 3:01 in Chicago, and eventually breaking the three-hour marathon barrier. She also discusses her 1:21 half-marathon, 5:24 mile, and the training changes that helped her become one of the fastest masters runners in the DFW running community. Her progress was far from easy. Kaitlin opens up about recovering from a torn IT band at the hip, a torn hamstring, and a torn calf. She explains why strength training, physical therapy, recovery, patience, and knowing when to rest have become just as important as running the miles. In this episode, Kaitlin and Chris discuss: Qualifying for Boston in her first marathon The journey from a 3:27 marathon to a 2:57 Balancing 70-mile training weeks with work and three children Training with Matt Campbell and the DFW running community Returning stronger after serious running injuries Strength training and injury prevention for masters runners Why every training cycle continues to build The friendships and support systems created through running Kaitlin’s story is a powerful reminder that improvement is rarely linear. Every training block, setback, recovery, and comeback contributes to the runner you become. Learn more about DFW Running Talk, local races, running clubs, training resources, and inspiring runner stories at www.dfwrunningtalk.com. Follow @dfwrunningtalk on Instagram, TikTok, and YouTube, and subscribe to DFW Running Talk on Spotify and Apple Podcasts.

    • Transcript
  • #122
    July 27 · 52 min

    Pete Johnson: 1:05:11 Half Marathon Debut, Steeplechase Success and a 2:16 CIM Goal

    Pete Johnson ran 1:05:11 in his first half marathon, averaging roughly five-minute-mile pace at the Houston Half Marathon. Now, the former University of Tulsa and Central Arkansas runner is preparing for his marathon debut at the California International Marathon, where he hopes to begin chasing the 2:16 Olympic Trials qualifying standard. In this episode of DFW Running Talk, Pete joins host Chris Detzel to share his complete running journey—from discovering cross country at Plano West to competing in NCAA track, cross country and the 3,000-meter steeplechase. Pete explains how an honest conversation with a college coach changed his mindset, pushed him to take training more seriously and helped him recognize his potential. He also discusses running 90–100-mile weeks, recording an 8:49 steeplechase, completing an 8K cross-country race in 23:39 and making the transition from collegiate racing to elite-level half-marathon and marathon training. The conversation covers: How Pete ran 1:05:11 in his half-marathon debut His Houston Half Marathon race strategy Training at the University of Tulsa and Central Arkansas The impact great coaches had on his development Steeplechase, cross-country and track racing High-mileage training and staying healthy Preparing for his first marathon at CIM His long-term Olympic Trials ambitions Balancing a physical therapy career with competitive running This episode is for runners interested in half-marathon training, marathon preparation, elite running, NCAA cross country, steeplechase, high-mileage training and the California International Marathon. Follow DFW Running Talk for conversations with runners, coaches, race directors and the people shaping the Dallas–Fort Worth running community. Website: www.dfwrunningtalk.com Newsletter: dfwrunningtalk.substack.com Instagram, TikTok and YouTube: @dfwrunningtalk

    • Transcript
  • #121
    July 21 · 42 min

    How Chris Shelton Found His Tribe with the McKinney Running Club

    Chris Detzel sits down with Chris Shelton of the McKinney Running Club for a story that starts with a competitive streak and turns into a full-blown love for running and community. Chris shares how it began in 2018 when his boss signed him up for the RAR 5K, why his very first training run (1.32 miles at a 16:23 pace) proves everyone starts somewhere, and how joining the McKinney Running Club in 2021 changed everything — from a bloody-shirt lesson on his second group run to jumping straight from a 10K to the Houston Marathon. We also get into running with a group to make the hard miles bearable, still chasing that sub-4-hour marathon, setting age-group PRs, what it actually takes to run a club, and the return of the McKinney Historic Half. Whether you're brand new or a seasoned marathoner, it's a reminder that the sport is about a lot more than pace. Subscribe to the newsletter: dfwrunningtalk.substack.com Rate, review, and let us know who we should feature next.

    • Transcript
  • #120
    July 13 · 39 min

    From a 5-Hour Marathon to 2:34 in Berlin | Troy Castle’s Work-Ethic Blueprint

    How did former SMU football player Troy Castle go from a painful five-hour first marathon to a 2:34 finish at the Berlin Marathon? On DFW Running Talk, host Chris Detzel sits down with the Dallas runner and two-time Irving Marathon winner to explore the marathon training, Ironman endurance base, Boston-qualifying breakthrough, Texas heat preparation, threshold workouts, and relentless consistency behind his transformation. Troy also explains how he balances serious running with three young children, why the Dallas running community changed his training, and what runners can learn from his pursuit of a sub-2:30 marathon.

    • Transcript
  • #119
    July 6 · 43 min

    Miranda Hyvl: 7x Boston, 23 Marathons, and Why She Built The Run House in Rockwall

    Miranda Hyvl started running 14 years ago with a couch-to-5K program as a busy mom just trying to get in shape. Today she's run 23 marathons, finished Boston seven times, checked off five of the six World Marathon Majors, and become an RRCA-certified coach — all while raising five kids in a blended family. But Miranda's biggest impact might be off the racecourse. When Rockwall's running community found itself scattered across grocery store parking lots with no home base, she and her husband built one: The Run House, a membership-based recovery lounge and running club that's become the heartbeat of running east of the lake. In this episode, Chris and Miranda talk about: How she went from a couch-to-5K program to a 3:26 marathon PR Balancing training with five kids — and the scheduling system that saved her marriage miles Why she tells first-time marathoners to throw out their time goals The origin story of The Run House and its recovery lounge (compression boots, sauna, and all) Her coaching philosophy: weekly customized plans, not 16-week templates from ChatGPT Boston rituals, chasing the 10-year streak, and the one major left before six stars The Rockwall Mile and what's next for racing in Rockwall Subscribe to the newsletter at dfwrunningtalk.substack.com and follow DFW Running Talk wherever you get your podcasts.

    • Transcript
  • #118
    May 25 · 53 min

    Neil Robinson: A 40-Minute PR and a Boston Qualifier at 52

    Neil Robinson started running seriously in his 40s, ran a 4:53 first marathon he swore would be his last, and then — at 52 — ran a 3:16:24 Boston Qualifier. This is the story of the slow build: years of run-walking, the nutrition and training lessons from the White Rock Running Co-op crowd, Pfitzinger plans, 1,960-mile years, and the mindset shift of learning to push through discomfort. A conversation about getting faster as you get older, the heart-health stakes that started it all, and why the running community is the real reason to keep showing up. Subscribe at dfwrunningtalk.substack.com

    • Transcript
  • #117
    May 20 · 17 min

    FIFA World Cup Countdown to the Cup 5K: Inside Dallas' Last Big Race Before the World Cup with Cindy Solomon & Eric Lindberg

    Eleven days before the 2026 FIFA World Cup kicks off in North Texas, runners and soccer fans are converging on The Sound at Cypress Waters for the Countdown to the Cup 5K — and in this episode, I get the full story from the two people making it happen. Cindy Solomon of the North Texas FIFA World Cup Organizing Committee and Eric Lindberg of On Your Left Marketing & Events join me to break down the race: the cup-shaped finisher medal, the brand-new USATF-certified course with a downhill finish, age group awards featuring the official Dallas World Cup ball, the Flying Saucer after-party, and the virtual option that's pulling registrations from across the country. We also go way beyond the 5K. Cindy walks through everything the Organizing Committee is doing — the FIFA Fan Festival at Fair Park (free, open to the public, 96 of 104 matches shown live), the Unity Cup youth soccer tournament, 26 mini pitches going into underserved communities, Dallas hosting nine matches including the July 14 semifinal, and why this is the first World Cup on U.S. soil since 1994. Eric also makes the case for why this is one of the last major DFW running events before the calendar goes dark for the summer — most races June through July moved their dates because of the World Cup. Register: https://www.countdowntothecup5k.com/ Save 15%: Code DFWRG Adults: $60 | Youth (12 & under): $30 Dallas 5K, FIFA World Cup 2026 Dallas, North Texas running events, Countdown to the Cup 5K, On Your Left Marketing, Cypress Waters race, USATF certified 5K Dallas, virtual 5K 2026.

    • Transcript
  • #116
    May 18 · 49 min

    Drew Martig: Self-Coaching to a 2:28 Marathon, Altitude Training in Flagstaff & Berlin Race Day

    Drew Martig started running at 27 — talked into a 5K by his CMO at Checkpoint Software. Less than a decade later, he ran 2:28 at the Berlin Marathon while self-coaching from his home in Flagstaff, Arizona. In this conversation, Chris Detzel and Drew (Tanium teammates and fellow distance runners) get into the nuts and bolts of building real marathon fitness on limited time. Drew opens up about leaving structured coaching to design his own plans, why he caps mileage around 70-90 per week, and how altitude in Flagstaff changes everything — including measurable shifts in red blood cell count and ferritin after just three weeks at 7,000 feet. We cover: → Drew's journey from no athletic background to 2:28 marathoner → Why "running by feel" beat structured pace-chasing for him → The Berlin Marathon: pre-race nerves, hip flexor niggles, negative splitting through 50,000 people → Self-coaching vs hiring a coach — the real tradeoffs → Why strength training prevents most running injuries → ChatGPT coaches, AI training plans, and the value of human mentorship → Coming back from September hernia surgery for a Chicago Marathon fall goal → Heat training in Texas vs altitude in Arizona → Why community matters even when you train alone A grounded, honest conversation between two working runners who balance demanding corporate careers, family life, and serious training goals. Subscribe to DFW Running Talk for new episodes weekly. Newsletter: dfwrunningtalk.substack.com

    • Transcript
  • #115
    May 11 · 47 min

    The DFW Running Legend: Nick Polito's 19-Year Journey From Nike+ iPod to Western States 100

    Nick Polito is a DFW running institution — 60 marathons, 30+ ultras, a 2:58 Boston PR, a Western States 100 buckle, and 19 straight years of high-mileage training. He founded Dallas Running Project, helped shape White Rock Running Club, and has paced 40-50 races for runners chasing their own goals. He's also the rare runner willing to tell on himself: in this episode, Nick shares the full story of banditing Boston, getting caught, and the suspension that followed — a cautionary tale he now uses to warn other runners. Chris Detzel and Nick cover everything from the early DRC days, the legendary "3:20 or Bust" Runner's World forum, training Nicole Bitter for her first 50-miler at Palo Duro, the super shoe revolution, and what it actually takes to stay motivated for two decades of running. If you've ever run at White Rock Lake, lined up at Plano Pacers, or wondered what the DFW running scene looked like before Pegasus existed — this is the episode. Listen, follow, and share with a running friend. 📬 www.dfwrunningtalk.substack.com

    • Transcript
  • #114
    May 5 · 36 min

    DFW Running OG Scott Manis on Ironman Training, Knee Surgeries & the WRRC Community That Changed Everything

    Scott Manis didn't start running until his early 40s, and he started in a swimsuit. Twenty years later, he's logged 45 marathons, five Boston appearances, a full Ironman, and become one of the most well-known and well-loved figures in the Dallas running scene through the White Rock Running Co-op. In this conversation, Chris and Scott trace the whole journey — from a lonely job transfer to West Palm Beach that accidentally ignited a running obsession, to a 4:33 first marathon that stung enough to spawn a second attempt just 12 weeks later (and nearly an hour faster). Scott talks honestly about what it felt like to finally stand on the Boston start line, what it took to drop from 3:38 to 3:09, and why the running community — not the miles — is the whole point. They also dig into the WRRC's famous "run my hood" summer tradition, two knee surgeries and the stubborn determination to pace a race right after recovery, what Ironman training actually does to your body and your soul, and Scott's now-iconic Gatorade bottle pre-race bathroom strategy that belongs in the runner's hall of fame. Scott is marathon-retired, officially. But if Tokyo calls — or one of his kids wants company at the start line — all bets are off. A great listen for anyone who started running late, anyone who's part of a running community, and honestly anyone who just loves hearing from a guy who's been quietly putting in the work for two decades.

    • Transcript
  • #113
    April 28 · 43 min

    Running Gave Me My Job" — Sergio Mena on Winning Dallas, Cowtown & Life in DFW

    Sergio Mena grew up running cross country in Spain, earned a full D1 scholarship to the University of Kentucky, got his MBA in Texas, and is now one of the most dominant half marathon runners in the DFW area — all while working full-time as an accounting manager. In this episode, Chris sits down with Sergio to talk about his journey from Spain to Kentucky to Texas, his years-long quest to win the BMW Dallas Half Marathon (which he finally achieved in December 2025), and how he followed it up with a win at the Cowtown Half Marathon. Sergio also tells the incredible story of how running literally got him his job — thanks to a Dallas Morning News article before the 2019 BMW Half. Topics include D1 college running, self-coached training, balancing racing with a full-time career, race strategy, and what keeps you lacing up when you've already hit your biggest goal. A great episode for DFW runners, half marathon fans, and anyone who runs because they just love it.

    • Transcript
Showing 1–20 of 21 episodes