[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"public-library:en-GB:workout:cycling-over-unders":3},{"slug":4,"sport":5,"category":6,"level":7,"intensity_unit":8,"modified_at":9,"author":10,"head":11,"equipment":14,"sources":17,"content":21,"facts":197,"blocks":382,"related":413},"cycling-over-unders","cycling","threshold","intermediate","watt","2026-10-25","Pierre Halloo",{"title":12,"description":13},"Over-unders: 3 × 12 min either side of FTP","Over-unders on the bike: 3 blocks of 12 min alternating 2 min at 94–96% and 1 min at 104–106% of FTP, no real recovery. Watts for FTPs of 200 to 300 W.",[15,16],"power_meter","smart_trainer",[18],{"citation":19,"url":20},"Carmichael C., OverUnder Intervals, CTS (Carmichael Training Systems)",null,{"h1":22,"summary":23,"purpose":34,"execution":78,"feel":100,"mistakes":107,"not_for":144,"faq":151,"evidence":188},"Over-under intervals (3 × 12 min)",{"type":24,"children":25},"root",[26],{"type":27,"tag":28,"props":29,"children":30},"element","p",{},[31],{"type":32,"value":33},"text","Over-unders: three 12-minute blocks alternating 2 minutes at 94–96% of FTP and 1 minute at 104–106%, with no real recovery. 36 minutes around threshold in 73 minutes. For learning to absorb changes of pace in races.",{"adaptation":35,"for_whom":47,"when":63},{"type":24,"children":36},[37,42],{"type":27,"tag":28,"props":38,"children":39},{},[40],{"type":32,"value":41},"Over-unders teach you to stay efficient through surges: a climb that kicks up, the bunch accelerating, a harder turn on the front. Each 'over' minute, just above threshold, builds fatigue; the two 'under' minutes that follow, just below, aren't a recovery: you keep riding hard, and your body has to absorb the extra without you easing off.",{"type":27,"tag":28,"props":43,"children":44},{},[45],{"type":32,"value":46},"The explanation often given, a better 'lactate shuttle' from one muscle to another, remains a hypothesis: no trial has tested this exact format. Its value is mainly practical. Racing is never ridden at constant power.",{"type":24,"children":48},[49],{"type":27,"tag":28,"props":50,"children":51},{},[52,54,61],{"type":32,"value":53},"Intermediate to advanced riders, after several threshold sessions in steady blocks, such as ",{"type":27,"tag":55,"props":56,"children":58},"a",{"href":57},"\u002Fen-GB\u002Flibrary\u002Fcycling\u002Fthreshold\u002Fcycling-threshold-intervals",[59],{"type":32,"value":60},"2 × 20",{"type":32,"value":62},". They suit riders who race in a bunch or on rolling courses. You need a recently measured FTP: a per cent either way changes both targets.",{"type":24,"children":64},[65],{"type":27,"tag":28,"props":66,"children":67},{},[68,70,76],{"type":32,"value":69},"One session of this kind a week at most during a build, in place of a threshold session. Keep at least one easy day before and after, and avoid the day before a race. To progress, lengthen the blocks from 8 to 15 minutes, then move to more contrasting alternations, such as the ",{"type":27,"tag":55,"props":71,"children":73},{"href":72},"\u002Fen-GB\u002Flibrary\u002Fcycling\u002Fthreshold\u002Fcycling-criss-cross",[74],{"type":32,"value":75},"criss-cross",{"type":32,"value":77},".",[79,86,93],{"type":24,"children":80},[81],{"type":27,"tag":28,"props":82,"children":83},{},[84],{"type":32,"value":85},"15 minutes building from 45 to 75% of FTP, in 5-minute steps. On a smart trainer, ERG mode copes well with changes every 1 to 2 minutes: it's on your side here.",{"type":24,"children":87},[88],{"type":27,"tag":28,"props":89,"children":90},{},[91],{"type":32,"value":92},"Three 12-minute blocks, each made of 4 × (2 minutes at 94–96% of FTP, then 1 minute at 104–106%), with 6 easy minutes at 50–60% between blocks. For an FTP of 250 W: 235 to 240 W, then 260 to 265 W. Each block finishes on an 'over', as Carmichael's version intends. Keep a steady cadence through the changes, and don't exceed the 'over' target: a few watts too many make the 'unders' impossible.",{"type":24,"children":94},[95],{"type":27,"tag":28,"props":96,"children":97},{},[98],{"type":32,"value":99},"10 very easy minutes at 40–55% of FTP. If the third block went badly, keep the same targets next time with 8-minute blocks.",{"type":24,"children":101},[102],{"type":27,"tag":28,"props":103,"children":104},{},[105],{"type":32,"value":106},"The 'overs' aren't the hardest part: it's coming back down only to 95% afterwards, without the relief of a proper recovery. The 'under' phase is very badly named. Guide: 8 to 9 out of 10 at the end of each block.",[108,117,126,135],{"title":109,"body":110},"Overshooting the 'overs'",{"type":24,"children":111},[112],{"type":27,"tag":28,"props":113,"children":114},{},[115],{"type":32,"value":116},"A minute at 115% instead of 105% seems harmless. But the 'unders' that follow become impossible, and the block falls apart. The session doesn't ask for heroic 'overs', it asks for 'unders' you can hold.",{"title":118,"body":119},"Turning the 'unders' into recovery",{"type":24,"children":120},[121],{"type":27,"tag":28,"props":122,"children":123},{},[124],{"type":32,"value":125},"Dropping to 85% for a breather removes the point of the session: carrying on hard just under threshold, with the fatigue of the previous minute.",{"title":127,"body":128},"Copying CTS's numbers as they are",{"type":24,"children":129},[130],{"type":27,"tag":28,"props":131,"children":132},{},[133],{"type":32,"value":134},"The original version refers to Carmichael's own field test: 86–90% and 95–100% of its power. Those numbers don't carry over to % of FTP. Here, it's about 95% and 105% of your FTP.",{"title":136,"body":137},"Adding them on top of a threshold session",{"type":24,"children":138},[139],{"type":27,"tag":28,"props":140,"children":141},{},[142],{"type":32,"value":143},"Over-unders replace a threshold session in your week, they don't add to it. Two sessions at this level within a few days is a lot of fatigue for little extra benefit.",{"prerequisites":145,"avoid_if":148},[146,147],"A recently measured FTP.","Several threshold sessions in steady blocks already done.",[149,150],"You're tired, or a race is planned for the next day.","You have doubts about your health: get medical advice before sustained hard efforts.",[152,161,170,179],{"question":153,"answer":154},"What power should I ride over-unders at?",{"type":24,"children":155},[156],{"type":27,"tag":28,"props":157,"children":158},{},[159],{"type":32,"value":160},"At 94–96% of FTP for the 'unders' and 104–106% for the 'overs'. For an FTP of 200 W, 188 to 192 W then 208 to 212 W; for 300 W, 282 to 288 W then 312 to 318 W. That's the common version, around 95 and 105%.",{"question":162,"answer":163},"Why finish each block on an 'over'?",{"type":24,"children":164},[165],{"type":27,"tag":28,"props":166,"children":167},{},[168],{"type":32,"value":169},"It's the instruction from Chris Carmichael, who popularised the session: finishing above threshold, already tired, is like the top of a climb or a surge in a race. It also forces you to keep something in reserve to accelerate right to the end of the block.",{"question":171,"answer":172},"Over-unders or threshold 2 × 20?",{"type":24,"children":173},[174],{"type":27,"tag":28,"props":175,"children":176},{},[177],{"type":32,"value":178},"Two by twenty first: constant power, simpler to hold. Over-unders add the changes of pace and are better preparation for rolling or bunch races. They replace a threshold session in your week rather than adding to it.",{"question":180,"answer":181},"Do over-unders improve lactate clearance?",{"type":24,"children":182},[183],{"type":27,"tag":28,"props":184,"children":185},{},[186],{"type":32,"value":187},"That's the usual explanation, but it remains a hypothesis: no scientific trial has tested this exact format. The value of over-unders is mainly practical: learning to hold threshold through surges, as in a race.",{"level":189,"text":190},"practice",{"type":24,"children":191},[192],{"type":27,"tag":28,"props":193,"children":194},{},[195],{"type":32,"value":196},"A format popularised by Chris Carmichael ('OverUnder Intervals', CTS), who insists every interval ends on an 'over'. The original version refers to CTS's own field test: 'under' at 86–90% and 'over' at 95–100% of that test's power, numbers that don't carry over as they are to % of FTP. The common version, widespread on training platforms, sits at about 95% and 105% of FTP. No scientific trial of this exact format has been found; the explanation usually given, the 'lactate shuttle', remains a hypothesis. The 6-minute recoveries between blocks, the warm-up and the cool-down are Wattson choices. Bottom line: very widely used, moderate confidence.",{"duration_seconds":198,"block_count":199,"load_estimate":200,"time_in_zone":201,"phases":211,"targets":259,"work":345,"profile":346},4380,30,77,[202,205,208],{"zone":203,"seconds":204},1,1620,{"zone":206,"seconds":207},2,600,{"zone":209,"seconds":210},4,2160,[212,228,253],{"role":213,"first_block":214,"last_block":206,"duration_seconds":215,"intensity_min":216,"intensity_max":217,"pattern":218},"warmup",0,900,"45","75",[219,223,226],{"kind":220,"zone":203,"duration_seconds":221,"intensity_min":216,"intensity_max":222,"cadence_min":20,"cadence_max":20},"step",300,"55",{"kind":220,"zone":206,"duration_seconds":221,"intensity_min":224,"intensity_max":225,"cadence_min":20,"cadence_max":20},"56","65",{"kind":220,"zone":206,"duration_seconds":221,"intensity_min":227,"intensity_max":217,"cadence_min":20,"cadence_max":20},"66",{"role":229,"first_block":230,"last_block":231,"duration_seconds":232,"intensity_min":233,"intensity_max":234,"pattern":235},"main",3,28,2880,"50","106",[236],{"kind":237,"count":230,"unit":238,"last_omitted":252},"repeat",[239,249],{"kind":237,"count":209,"unit":240,"last_omitted":248},[241,245],{"kind":220,"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244,"cadence_min":20,"cadence_max":20},120,"94","96",{"kind":220,"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234,"cadence_min":20,"cadence_max":20},60,"104",false,{"kind":220,"zone":203,"duration_seconds":250,"intensity_min":233,"intensity_max":251,"cadence_min":20,"cadence_max":20},360,"60",true,{"role":254,"first_block":255,"last_block":255,"duration_seconds":207,"intensity_min":256,"intensity_max":222,"pattern":257},"cooldown",29,"40",[258],{"kind":220,"zone":203,"duration_seconds":207,"intensity_min":256,"intensity_max":222,"cadence_min":20,"cadence_max":20},[260,276,290,302,315,325,337],{"intensity_min":247,"intensity_max":234,"zone":209,"total_seconds":261,"step_seconds":246,"roles":262,"watts":263,"paces":275},720,[229],[264,268,272],{"ftp":265,"watts_min":266,"watts_max":267},200,208,212,{"ftp":269,"watts_min":270,"watts_max":271},250,260,265,{"ftp":221,"watts_min":273,"watts_max":274},312,318,[],{"intensity_min":243,"intensity_max":244,"zone":209,"total_seconds":277,"step_seconds":242,"roles":278,"watts":279,"paces":289},1440,[229],[280,283,286],{"ftp":265,"watts_min":281,"watts_max":282},188,192,{"ftp":269,"watts_min":284,"watts_max":285},235,240,{"ftp":221,"watts_min":287,"watts_max":288},282,288,[],{"intensity_min":227,"intensity_max":217,"zone":206,"total_seconds":221,"step_seconds":221,"roles":291,"watts":292,"paces":301},[213],[293,296,298],{"ftp":265,"watts_min":294,"watts_max":295},132,150,{"ftp":269,"watts_min":297,"watts_max":281},165,{"ftp":221,"watts_min":299,"watts_max":300},198,225,[],{"intensity_min":224,"intensity_max":225,"zone":206,"total_seconds":221,"step_seconds":221,"roles":303,"watts":304,"paces":314},[213],[305,308,311],{"ftp":265,"watts_min":306,"watts_max":307},112,130,{"ftp":269,"watts_min":309,"watts_max":310},140,163,{"ftp":221,"watts_min":312,"watts_max":313},168,195,[],{"intensity_min":233,"intensity_max":251,"zone":203,"total_seconds":261,"step_seconds":250,"roles":316,"watts":317,"paces":324},[229],[318,320,322],{"ftp":265,"watts_min":319,"watts_max":242},100,{"ftp":269,"watts_min":321,"watts_max":295},125,{"ftp":221,"watts_min":295,"watts_max":323},180,[],{"intensity_min":216,"intensity_max":222,"zone":203,"total_seconds":221,"step_seconds":221,"roles":326,"watts":327,"paces":336},[213],[328,331,334],{"ftp":265,"watts_min":329,"watts_max":330},90,110,{"ftp":269,"watts_min":332,"watts_max":333},113,138,{"ftp":221,"watts_min":335,"watts_max":297},135,[],{"intensity_min":256,"intensity_max":222,"zone":203,"total_seconds":207,"step_seconds":207,"roles":338,"watts":339,"paces":344},[254],[340,342,343],{"ftp":265,"watts_min":341,"watts_max":330},80,{"ftp":269,"watts_min":319,"watts_max":333},{"ftp":221,"watts_min":242,"watts_max":297},[],{"intensity_min":243,"intensity_max":234,"zone":209,"seconds":210},[347,348,350,352,354,356,357,358,359,360,361,362,363,364,365,366,367,368,369,370,371,372,373,374,375,376,377,378,379,380],{"zone":203,"duration_seconds":221,"intensity":233},{"zone":206,"duration_seconds":221,"intensity":349},"60.5",{"zone":206,"duration_seconds":221,"intensity":351},"70.5",{"zone":209,"duration_seconds":242,"intensity":353},"95",{"zone":209,"duration_seconds":246,"intensity":355},"105",{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":203,"duration_seconds":250,"intensity":222},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":203,"duration_seconds":250,"intensity":222},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":209,"duration_seconds":242,"intensity":353},{"zone":209,"duration_seconds":246,"intensity":355},{"zone":203,"duration_seconds":207,"intensity":381},"47.5",[383,384,385,386,387,388,389,390,391,392,393,394,395,396,397,398,399,400,401,402,403,404,405,406,407,408,409,410,411,412],{"zone":203,"duration_seconds":221,"intensity_min":216,"intensity_max":222},{"zone":206,"duration_seconds":221,"intensity_min":224,"intensity_max":225},{"zone":206,"duration_seconds":221,"intensity_min":227,"intensity_max":217},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":203,"duration_seconds":250,"intensity_min":233,"intensity_max":251},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":203,"duration_seconds":250,"intensity_min":233,"intensity_max":251},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":209,"duration_seconds":242,"intensity_min":243,"intensity_max":244},{"zone":209,"duration_seconds":246,"intensity_min":247,"intensity_max":234},{"zone":203,"duration_seconds":207,"intensity_min":256,"intensity_max":222},[414,467,532],{"slug":415,"sport":5,"category":6,"level":7,"intensity_unit":8,"name":416,"duration_seconds":417,"profile":418,"relation":466},"cycling-criss-cross","Criss-cross threshold (20 min)",2700,[419,420,421,422,424,426,428,429,430,431,432,433,434,435,436,437,438,439,440,441,442,443,444,445,446,447,448,449,450,451,452,453,454,455,456,457,458,459,460,461,462,463,464,465],{"zone":203,"duration_seconds":221,"intensity":233},{"zone":206,"duration_seconds":221,"intensity":349},{"zone":206,"duration_seconds":221,"intensity":351},{"zone":209,"duration_seconds":199,"intensity":423},"95.5",{"zone":209,"duration_seconds":199,"intensity":425},"97.5",{"zone":209,"duration_seconds":199,"intensity":427},"100.5",{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":247},{"zone":209,"duration_seconds":199,"intensity":427},{"zone":209,"duration_seconds":199,"intensity":425},{"zone":209,"duration_seconds":199,"intensity":423},{"zone":203,"duration_seconds":207,"intensity":381},"same_family",{"slug":468,"sport":5,"category":6,"level":7,"intensity_unit":8,"name":469,"duration_seconds":470,"profile":471,"relation":466},"cycling-sixty-sixty","60\u002F60 around threshold 6 × 8 min",5280,[472,473,474,475,478,480,481,482,483,484,485,486,487,488,489,490,491,492,493,494,495,496,497,498,499,500,501,502,503,504,505,506,507,508,509,510,511,512,513,514,515,516,517,518,519,520,521,522,523,524,525,526,527,528,529,530,531],{"zone":203,"duration_seconds":221,"intensity":233},{"zone":206,"duration_seconds":221,"intensity":349},{"zone":206,"duration_seconds":221,"intensity":351},{"zone":476,"duration_seconds":246,"intensity":477},5,"110",{"zone":230,"duration_seconds":246,"intensity":479},"90",{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":203,"duration_seconds":323,"intensity":222},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":203,"duration_seconds":323,"intensity":222},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":203,"duration_seconds":323,"intensity":222},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":203,"duration_seconds":323,"intensity":222},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":203,"duration_seconds":323,"intensity":222},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":476,"duration_seconds":246,"intensity":477},{"zone":230,"duration_seconds":246,"intensity":479},{"zone":203,"duration_seconds":207,"intensity":381},{"slug":533,"sport":5,"category":6,"level":7,"intensity_unit":8,"name":534,"duration_seconds":535,"profile":536,"relation":545},"cycling-threshold-intervals","Threshold 2 × 20 min",4500,[537,538,539,540,542,543,544],{"zone":203,"duration_seconds":221,"intensity":233},{"zone":206,"duration_seconds":221,"intensity":349},{"zone":206,"duration_seconds":221,"intensity":351},{"zone":209,"duration_seconds":541,"intensity":425},1200,{"zone":203,"duration_seconds":207,"intensity":222},{"zone":209,"duration_seconds":541,"intensity":425},{"zone":203,"duration_seconds":207,"intensity":381},"easier"]